Author Archives: Dr. Darrin

Teaching Small Children to Write

Teaching a child to write is an interesting experience. In this post, I will share some basics ideas on one way this can be done.

To Read or not to Read

Often writing is taught after the child has learned to read. A major exception to this is the Montessori method of reading. For Montessori, a child should learn to write before reading. This is probably because writing is a more tactile experience when compared to reading and Montessori was a huge proponent of experiential learning. In addition, if you can write you can definitely read under this assumption.

Generally, I teach young children how to read first. This is because I want the child to know the letters before trying to write them.

The Beginning

If the child is already familiar with the basics of reading writing is probably more about hand-eye coordination than anything else. The first few letters are quite the experience. This is affected by age as well. Smaller children will have much more difficulty with writing than older children.

A common strategy to motivate a child to write is to have them first learn to spell their name. This can work depending on how hard the child’s name is to spell. A kid named “Dan” will master writing his name quickly. However, a kid with a longer name or a transliterated name from another language is going to have a tough time. I knew one student who misspelled their name for almost a year and a half because it was so hard to write in English.

A common way to teach actually writing is to allow the child to trace the words on dot paper. By doing this they develop the muscle memory for writing. Once this is successful the child will then attempt to write the letters with the tracing paper. This process can easily take a year.

Sentences and Paragraphs

After,  they learn to write letters and words it is time to begin writing sentences. A six-year-old, with good penmanship, will probably not be able to write a sentence with support. Writing and spelling and different skills initially and it is the adult’s job to provide support for the spelling aspect as the child explains what they want to write about.

With help, children can create short little stories that may be one to two paragraphs in length. Yet they will still need a lot of support to do this.

By eight years of age, a child can probably write a paragraph on their own about simple concepts or stories. This is when the teaching and learning can really get interesting as the child can now write to learn instead of focusing on learning to write.

Conclusion

Writing is a skill that is hard to find these days. With so many other forms of communication, writing is not a skill that children want to focus on. Nevertheless, learning to write by basic literacy is an excellent way to develop communication skills and interact with people in situations where face-to-face contact is not possible.

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Homeschooling Concerns

Parents frequently have questions about homeschooling. In this post, we look at three common questions related to homeschooling.

  1. How do you know if your child has learned
  2. What do you do about socializing
  3. What about college

How do You know if they Learned

One definition of learning is a change in observable behavior. In other words, one-way a parent can know that their child is learning is through watching for changes in behavior. For example, you are teaching addition and the child begins to do addition on their own. It is evidence that they have learned something. There is no need for standardized testing in order to indicate this.

A lot of the more advanced forms of assessment including standardized test was created in order to assess the progress of a huge number of students. In the context of homeschooling with only a few students, such rigorous measures are unnecessary. governments need sophisticated measures of achievement because of the huge populations that they serve which would be inappropriate when dealing with one or two elementary students.

Another way to know what your child has learned is to look at what they are studying right now. For example, if my child is reading I know that they have probably mastered the alphabet. Otherwise, how could the read? I also know that they probably have mastered the most of the phonics. In other words, current struggles are an indication of what was mastered before.

What about Socializing

The answer to this question really depends on your position on socializing. Many parents want their child to act like other children. For example, if my child is 7 I want him to act like other 7-year-olds.

Other parents want their child to learn how to act like an adult. For them, they want their 7-year-old child to imitate the behavior of them (the parents) rather than the behavior of other 7-year-olds. A child will only rise to the expectations of those around them. Being around children encourages childish behavior because that’s the example. Again for many parents, this is what they want, however, others see this differently.

The reality is that until middle-age most of the people we interact with are older than us. As such, it is beneficial for a child to spend a large amount of time around people who are older than them and understand the importance of setting an example that can be imitated.

All socializing is not the same. Adult-to-child socializing provides a child with an example of how to be an adult rather than how to be a child. Besides, most small children would love to be around their parents all day. They only grow to love friends so much because those are the people who give them the most attention.

What about College

This question is the hardest to answer as it depends on context a great deal. Concerns with college can be alleviated by having the child take the GED in the US or local college entrance examinations in other countries.

It is also important to keep careful records of what the child studies during high school. Most colleges do not care about K-8 learning but really want to know what happens during grades 9-12. Keep records of the courses the child took as well as the grades. It will also be necessary to take the SAT or ACT in most countries as well.

Conclusion

Homeschooling is an option for people who want to spend the maximum amount of time possible with their children. Concerns about learning, socializing, and college are unnecessary if the parents are willing to thoroughly dedicate themselves and provide their children with a learning environment that develops their children wholistically.

What it Takes to Homeschool

Some may be wondering what does it take to homeschool. Below are some characteristics of the homeschool.

Time management

Being able to adhere to a schedule is a prerequisite for homeschooling. It is tempting to just kind of doing things whenever when you have this kind of freedom. However, in order to be successful, you have to hold yourself responsibility like your boss would. This is difficult for most people who are not used to autonomy.

This is not to say there should be no flexibility. Rather, the schedule should not be cheated because of laziness. There must be a set schedule for studying for the sake of behavior management of the children. If the child doesn’t know what to expect they may challenge you when you flippantly decide they need to study. Consistency is a foundational principle of homeschooling.

Discipline

Discipline means being able to do something even when you do not feel like doing it. In homeschooling, you have to teach whether you want to or not. Remember, sometimes we had to work at our jobs when we didn’t feel like it and the same with teaching in the home. If you’re tired you still have to teach, if you’re a little sick you still have to teach, if you’re angry you still have to teach.

The child is relying on you to provide them with the academic skills needed to compete in the world. This cannot be neglected for trivial reasons. Lesson plans are key. Either buy them or make them. Keep track of completed assignment and note the progress of the student.

Toughness

As a homeschooling parent, you are the only authority in the child’s life. This means all discipline falls under your jurisdiction. One reasons parents enjoy sending their kids to school is to burden the public school teachers with their own child’s poor behavior. “Let the school deal with him” is a common comment I have heard when I was a k12 teacher. However, when you teach as a homeschool parent only you have the pleasure of disciplining your child.

Discipline is not only about taking away privileges and causing general suffering for unacceptable behavior. Discipline also includes communicating clearly with your child to prevent poor behavior, have clear rules that are always enforced, as well as providing a stable environment in which to study.

Patience

Homeschooling also requires patience. For example, you are teaching a basic first-grade math concept to your child that takes several weeks for them to learn.  Naturally, you start to get angry with the child and yourself for the lack of progress. You may even begin to question if you have what it takes to do this. However, after waiting for what seems an eternity they child finally gets it.

This is the reality of homeschooling. No matter how bad you think you are the child will eventually get it when they are ready. This requires patience in the parent and some confidence in their own ability to help their child to grow.

Conclusion

There are many more ideas I could share. However, this is sufficient for now. In general, I would not recommend homeschooling for the typical family as the above traits are usually missing in the parents. Many parents want to homeschool for emotional reasons. The problem with this is that when they feel bad they will not want to continue the experience. Homeschooling can involve love but it must transcend emotions in order to endure for several years.

Teaching Math in the Homeschool

Teaching a child to count and do simple math is much more challenge then many would believe. Below is a simple process that I accidentally developed from working with kindergarten home-school student for two years. Keep in mind that often these steps overlapped.

  1. Number recognition
  2. Counting
  3. Counting with manipulatives
  4. Flashcards with larger numbers
  5. Writing numbers
  6. Adding with manipulatives
  7. Subtraction with manipulatives
  8. Visual math

1.  Number Recognition

Number recognition simple involved the use of flashcards with the child. I would hold up a number and tell the child what the number was. Memorizing is perhaps one of the easiest things the young mind can do as critical thinking comes much later. This initial process probably took about 6 months with a four-year-old to learn number 1-20.

2. Counting

With the numbers memorized, the next step was to actually learn to count. I did this by holding up the same flashcards. After the child identify what number it was I would then flip the flashcard over and have them count the number of objects on the card. My goal was to have them make a connection between the abstract number and the actual amount that could be seen and counted.

Again it took about six months for the four and half-year-old student to master this from numbers 1-20. It was a really stressful six months.

3. Counting with Manipulatives

The next few steps happen concurrently for the most part. I started to have the student count with manipulatives. I would show or say a number and expect the student to count the correct number using the manipulatives. This was done with numbers 1-20 only.

4. Flashcards with Larger Numbers 

At the same time, I worked with the student to learn numbers beyond 20. This was strictly for memorization purposes. This continued from 4.5 to 6 years of age. Eventually, the child could identify numbers 1-999. However, the never discovered the pattern of counting. By pattern, I mean how the 0-9 cycle repeats in the tens, how the 1-9 cycle repeats for the tens when moving to 100s, etc. The child only knew the numbers through brute memorization.

5. Writing Numbers

Writing numbers was used as preparation for doing addition. It was as simple as giving the student some numbers to trace on paper. It took about 8 months for the student to write numbers with any kind of consistency.

6. Adding with Manipulatives

This involved me writing a math problem and having the student solve the problem use manipulatives. For example, 2 + 2 would be solved by having the student count two manipulatives and then count two more and then count the total.

My biggest concern was having the child understand the + and = sign. The plus sign was easy but the equal sign was mysterious for a long time. However, the learning rate was picking up and the kid learn this in about 3 months

7. Subtraction with Manipulatives

Same as above but only took one month to learn

8. Visual Math

At this stage,  the child was doing worksheets on their own. Manipulatives were allowed as a crutch to get through the problems. However, the child was now being encouraged to use their fingers for counting purposes. This was a disaster for several weeks as the lack the coordination to open and close the fingers independent of each other.

Conclusion

This entire process took two years to complete from ages 4-6 working with the child one-on-one. By the age of six, the child could add and subtract anything from 1-30 and was ready for 1st grade.

I would recommend waiting longer to start math with a child. Being 4 was probably too young for this particular child. Better to wait untili 5 or 6 to learn numbers and counting. There more danger in starting early then there is in starting late.

Confusing Words for Small Children

In this post, we will look at some commonly used words that can bring a great deal of frustration to adults when communicating with small children. The terms are presented in the following categories

  • Deictic terms
  • Interrogatives
  • Locational terms
  • Temporal terms

Deictic Terms

Deictic terms fall under the umbrella of pragmatic development or understanding of the context in which words are used. Examples of deictic terms include such words as this, that, these, those, here, there, etc. What makes these words confusing for young children and even ESL speakers is that the meaning of these words depends on the context. Below is a clear way to communicate followed by a way that is unclear using a deixis term

Clear communication: Take the book
Unclear communication: Take that

The first sentence makes it clear what to take which in this example is the book. However, for a child or ESL speaker, the second sentences can be mysterious. What does “that” mean. It takes pragmatic or contextual knowledge to determine what “that” is referring to in the sentence. Children usually cannot figure this out while an ESL speaker will watch the body language (nonlinguistic cues) of the speaker to figure this out.

Interrogatives

A unique challenge for children is understanding interrogatives. These are such words as who, what, where, when, and why. The challenge with these questions is they involve explaining the cause, time, and or reasons. Many parents have asked the following question without receiving an adequate answer

Why did you take the book?

The typical 3-year old is going to wonder what the word “why” means. Off course, you can combine a deictic term with an interrogative and completely lose a child

Why did you do that?

Locational Terms

Locational terms are prepositions words such as in, under, above, behind etc. These words can be challenging for young children because they have to understand the perspective of the person speaking. Below is an example.

Put the book under the table.

Naturally, the child is trying to understand what “under” means. We can also completely confuse a child by using terms from all the categories we have discussed so far.

Why did you put that under the table?

This sentence would probably be unclear to many native speakers. The ambiguity is high especially with the term “that” included.

Temporal Terms

Temporal terms are about time. Commonly used words include before, after, while, etc. These terms are difficult for children because young children do not quite grasp the concept of time. Below is an example of a sentence with a temporal term.

Before, dinner, grab the book

The child is probably wondering when they are supposed to get the book. Naturally, we can combine all of our terms to make a truly nightmarish sentence.

Why did you put that under the table after dinner?

Conclusion

The different terms mentioned here are terms that can cause frustration when trying to communicate. To alleviate, these problems parents and teachers should avoid these terms when possible by using nouns. In addition, using body language to indicate position or pointing to whatever you are talking about can help young children to infer the meaning

Additive Assumption and Multiple Regression

In regression, one of the assumptions is the additive assumption. This assumption states that the influence of a predictor variable on the dependent variable is independent of any other influence. However, in practice, it is common that this assumption does not hold.

In this post, we will look at how to address violations of the additive assumption through the use of interactions in a regression model.

An interaction effect is when you have two predictor variables whose effect on the dependent variable is not the same. As such, their effect must be considered simultaneously rather than separately. This is done through the use of an interaction term. An interaction term is the product of the two predictor variables.

Let’s begin by making a regular regression model with an interaction. To do this we will use the “Carseats” data from the “ISLR” package to predict “Sales”. Below is the code.

library(ISLR);library(ggplot2)
data(Carseats)
saleslm<-lm(Sales~.,Carseats)
summary(saleslm)
## 
## Call:
## lm(formula = Sales ~ ., data = Carseats)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -2.8692 -0.6908  0.0211  0.6636  3.4115 
## 
## Coefficients:
##                   Estimate Std. Error t value Pr(>|t|)    
## (Intercept)      5.6606231  0.6034487   9.380  < 2e-16 ***
## CompPrice        0.0928153  0.0041477  22.378  < 2e-16 ***
## Income           0.0158028  0.0018451   8.565 2.58e-16 ***
## Advertising      0.1230951  0.0111237  11.066  < 2e-16 ***
## Population       0.0002079  0.0003705   0.561    0.575    
## Price           -0.0953579  0.0026711 -35.700  < 2e-16 ***
## ShelveLocGood    4.8501827  0.1531100  31.678  < 2e-16 ***
## ShelveLocMedium  1.9567148  0.1261056  15.516  < 2e-16 ***
## Age             -0.0460452  0.0031817 -14.472  < 2e-16 ***
## Education       -0.0211018  0.0197205  -1.070    0.285    
## UrbanYes         0.1228864  0.1129761   1.088    0.277    
## USYes           -0.1840928  0.1498423  -1.229    0.220    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 1.019 on 388 degrees of freedom
## Multiple R-squared:  0.8734, Adjusted R-squared:  0.8698 
## F-statistic: 243.4 on 11 and 388 DF,  p-value: < 2.2e-16

The results are rather excellent for the social sciences. The model explains 87.3% of the variance in “Sales”. The current results that we have are known as main effects. These are effects that directly influence the dependent variable. Most regression models only include main effects.

We will now examine an interaction effect between two continuous variables. Let’s see if there is an interaction between “Population” and “Income”.

saleslm1<-lm(Sales~CompPrice+Income+Advertising+Population+Price+Age+Education+US+
                     Urban+ShelveLoc+Population*Income, Carseats)
summary(saleslm1)
## 
## Call:
## lm(formula = Sales ~ CompPrice + Income + Advertising + Population + 
##     Price + Age + Education + US + Urban + ShelveLoc + Population * 
##     Income, data = Carseats)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -2.8699 -0.7624  0.0139  0.6763  3.4344 
## 
## Coefficients:
##                     Estimate Std. Error t value Pr(>|t|)    
## (Intercept)        6.195e+00  6.436e-01   9.625   <2e-16 ***
## CompPrice          9.262e-02  4.126e-03  22.449   <2e-16 ***
## Income             7.973e-03  3.869e-03   2.061   0.0400 *  
## Advertising        1.237e-01  1.107e-02  11.181   <2e-16 ***
## Population        -1.811e-03  9.524e-04  -1.901   0.0580 .  
## Price             -9.511e-02  2.659e-03 -35.773   <2e-16 ***
## Age               -4.566e-02  3.169e-03 -14.409   <2e-16 ***
## Education         -2.157e-02  1.961e-02  -1.100   0.2722    
## USYes             -2.160e-01  1.497e-01  -1.443   0.1498    
## UrbanYes           1.330e-01  1.124e-01   1.183   0.2375    
## ShelveLocGood      4.859e+00  1.523e-01  31.901   <2e-16 ***
## ShelveLocMedium    1.964e+00  1.255e-01  15.654   <2e-16 ***
## Income:Population  2.879e-05  1.253e-05   2.298   0.0221 *  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 1.013 on 387 degrees of freedom
## Multiple R-squared:  0.8751, Adjusted R-squared:  0.8712 
## F-statistic:   226 on 12 and 387 DF,  p-value: < 2.2e-16

The new contribution is at the bottom of the coefficient table and is the “Income:Population” coefficient. What this means is “the increase of Sales given a one unit increase in Income and Population simultaneously” In other words the “Income:Population” coefficient looks at their combined simultaneous effect on Sales rather than just their independent effect on Sales.

This makes practical sense as well. The larger the population the more available income and vice versa. However, for our current model, the improvement in the r-squared is relatively small. The actual effect is a small increase in sales. Below is a graph of income and population by sales. Notice how the lines cross. This is a visual of what an interaction looks like. The lines are not parallel by any means.

ggplot(data=Carseats, aes(x=Income, y=Sales, group=1)) +geom_smooth(method=lm,se=F)+ 
        geom_smooth(aes(Population,Sales), method=lm, se=F,color="black")+xlab("Income and Population")+labs(
                title="Income in Blue Population in Black")

We will now repeat this process but this time using a categorical variable and a continuous variable. We will look at the interaction between “US” location (categorical) and “Advertising” (continuous).

saleslm2<-lm(Sales~CompPrice+Income+Advertising+Population+Price+Age+Education+US+
                     Urban+ShelveLoc+US*Advertising, Carseats)
summary(saleslm2)
## 
## Call:
## lm(formula = Sales ~ CompPrice + Income + Advertising + Population + 
##     Price + Age + Education + US + Urban + ShelveLoc + US * Advertising, 
##     data = Carseats)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -2.8531 -0.7140  0.0266  0.6735  3.3773 
## 
## Coefficients:
##                     Estimate Std. Error t value Pr(>|t|)    
## (Intercept)        5.6995305  0.6023074   9.463  < 2e-16 ***
## CompPrice          0.0926214  0.0041384  22.381  < 2e-16 ***
## Income             0.0159111  0.0018414   8.641  < 2e-16 ***
## Advertising        0.2130932  0.0530297   4.018 7.04e-05 ***
## Population         0.0001540  0.0003708   0.415   0.6782    
## Price             -0.0954623  0.0026649 -35.823  < 2e-16 ***
## Age               -0.0463674  0.0031789 -14.586  < 2e-16 ***
## Education         -0.0233500  0.0197122  -1.185   0.2369    
## USYes             -0.1057320  0.1561265  -0.677   0.4987    
## UrbanYes           0.1191653  0.1127047   1.057   0.2910    
## ShelveLocGood      4.8726025  0.1532599  31.793  < 2e-16 ***
## ShelveLocMedium    1.9665296  0.1259070  15.619  < 2e-16 ***
## Advertising:USYes -0.0933384  0.0537807  -1.736   0.0834 .  
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 1.016 on 387 degrees of freedom
## Multiple R-squared:  0.8744, Adjusted R-squared:  0.8705 
## F-statistic: 224.5 on 12 and 387 DF,  p-value: < 2.2e-16

Again, you can see that when the store is in the US you have to also consider the advertising budget as well. When these two variables are considered there is a slight decline in sales. What this means in practice is that advertising in the US is not as beneficial as advertising outside the US.

Below you can again see a visual of the interaction effect when the lines for US yes and no cross each other in the plot below.

ggplot(data=Carseats, aes(x=Advertising, y=Sales, group = US, colour = US)) +
        geom_smooth(method=lm,se=F)+scale_x_continuous(limits = c(0, 25))+scale_y_continuous(limits = c(0, 25))

Lastly, we will look at an interaction effect for two categorical variables.

saleslm3<-lm(Sales~CompPrice+Income+Advertising+Population+Price+Age+Education+US+
                     Urban+ShelveLoc+ShelveLoc*US, Carseats)
summary(saleslm3)
## 
## Call:
## lm(formula = Sales ~ CompPrice + Income + Advertising + Population + 
##     Price + Age + Education + US + Urban + ShelveLoc + ShelveLoc * 
##     US, data = Carseats)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -2.8271 -0.6839  0.0213  0.6407  3.4537 
## 
## Coefficients:
##                         Estimate Std. Error t value Pr(>|t|)    
## (Intercept)            5.8120748  0.6089695   9.544   <2e-16 ***
## CompPrice              0.0929370  0.0041283  22.512   <2e-16 ***
## Income                 0.0158793  0.0018378   8.640   <2e-16 ***
## Advertising            0.1223281  0.0111143  11.006   <2e-16 ***
## Population             0.0001899  0.0003721   0.510   0.6100    
## Price                 -0.0952439  0.0026585 -35.826   <2e-16 ***
## Age                   -0.0459380  0.0031830 -14.433   <2e-16 ***
## Education             -0.0267021  0.0197807  -1.350   0.1778    
## USYes                 -0.3683074  0.2379400  -1.548   0.1225    
## UrbanYes               0.1438775  0.1128171   1.275   0.2030    
## ShelveLocGood          4.3491643  0.2734344  15.906   <2e-16 ***
## ShelveLocMedium        1.8967193  0.2084496   9.099   <2e-16 ***
## USYes:ShelveLocGood    0.7184116  0.3320759   2.163   0.0311 *  
## USYes:ShelveLocMedium  0.0907743  0.2631490   0.345   0.7303    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 1.014 on 386 degrees of freedom
## Multiple R-squared:  0.8753, Adjusted R-squared:  0.8711 
## F-statistic: 208.4 on 13 and 386 DF,  p-value: < 2.2e-16

In this case, we can see that when the store is in the US and the shelf location is good it has an effect on Sales when compared to a bad location. The plot below is a visual of this. However, it is harder to see this because the x-axis has only two categories

ggplot(data=Carseats, aes(x=US, y=Sales, group = ShelveLoc, colour = ShelveLoc)) +
        geom_smooth(method=lm,se=F)

Conclusion

Interactions effects are a great way to fine-tune a model, especially for explanatory purposes. Often, the change in r-square is not strong enough for prediction but can be used for nuanced understanding of the relationships among the variables.

Concepts to Consider for Model Development

When assessing how to conduct quantitative data analysis there are several factors to consider. In this post, we look at common either-or choices in data analysis. The concepts are as follows

  • Parametric vs Non-Parametric
  • Bias vs Variance
  • Accuracy vs Interpretability
  • Supervised vs Unsupervised
  • Regression vs Classifications

Parametric vs Non-Parametric

Parametric models make assumptions about the shape of a function. Often, the assumption is that the function is a linear in nature such as in linear regression. Making this assumption makes it much easier to estimate the actual function of a model.

Non-parametric models do not make any assumptions about the shape of the function. This allows the function to take any shape possible. Examples of non-parametric models include decision trees, support vector machines, and artificial neural networks.

The main concern with non-parametric models is they require a huge dataset when compared to parametric models.

Bias vs Variance Tradeoff

In relation to parametric and non-parametric models is the bias-variance tradeoff. A bias model is simply a model that does not listen to the data when it is tested on the test dataset. The function does what it wants as if it was not trained on the data. Parametric models tend to suffer from high bias.

Variance is the change in the function if it was estimated using new data. Variance is usually much higher in non-parametric models as they are more sensitive to the unique nature of each dataset.

Accuracy vs Interpretability 

It is also important to determine what you want to know. If your goal is accuracy then a complicated model may be more appropriate. However, if you want to infer and make conclusions about your model then it is preferred to make a simpler model that can be explained.

A model can be made simpler or more complex through the inclusion of more features or the use of a more complex algorithm. For example, regression is much easier to interpret than artificial neural networks.

Supervised vs Unsupervised

Supervised learning is learning that involves a dependent variable. Examples of supervised learning include regression, support vector machines, K nearest neighbor, and random forest.

Unsupervised learning involves a dataset that does not have a dependent variable. In this situation,  you are looking for patterns in the data. Examples of this include kmeans, principal component analysis, and cluster analysis.

Regression vs Classifications

Lastly, a problem can call for regression or classification. A regression problem involves a numeric dependent variable. A classification problem has a categorical dependent variable. Almost all models that are used for supervised machine learning can address regression or classification.

For example, regression includes numeric regression and logistic regression for classification. K nearest neighbor can do both as can random forest, support vector machines, and artificial neural networks.

Ways to Comprehend Academic Texts

In this post, we will look at some practical ways to better understand an academic text. The tips are broken down into three sections which are, what to do before, during, and after reading.

Before Reading

Read the Preface. The preface lays out the entire scope of the book. It provides the framework in which you can place the details of the chapters. This is critical in order to put the pieces together to make use of them. Almost all students skip this as it is normally not assigned reading. This step is only done before reading the first chapter of a text.

Read the Chapter titles. The chapter titles give you an idea of what the chapter is about. Again it helps you to zoom down one level to understand the subject of the book from one aspect of it. Again, most students fly past this when the chapter title provides clear clues as to what to expect in the text

Read the Objectives. The objectives tell you what you are going to visit in the chapter. They serve as signposts of what to expect and provide a framework for placing the details of the text.

Read the Chapter Headings. An academic text is broken down into chapters which are broken down into headings. Examining the headings provides more information about the chapter and the book. I also should mention that often the objectives and the headings of a book are the same with slight rewording. This seems lazy but is actually much clearer than when they two are not similar.

Look at the visuals (tables, graphs, pictures). Visuals summarize critical information. It is easy for anybody to become overwhelmed when reading a text. Therefore, visuals are created to summarize the most important information. Just like figure 1.2 above.

If you do these things you now know what to expect when you read. You are also beginning to develop an idea of what you did not know about the given subject. This leads to the next major point.

Ask Questions. After this inspection of the text, you should do the following.

  • Decide what you already know about this topic
  • Decide what you want to know about this topic and make questions

This two-step process prepares you for connecting your current level of understanding with the new knowledge within the text. You know what is a review for you and you focus on finding answers to the concepts and idea that are new for you.

During Reading

 After all of this preparatory work, it is now time to read. Having done all this you already know the following

  • Title of the chapter
  • Major headings/objectives of the chapter
  • What you already know about this subject
  • What you do not know about this subject

Now you read the text and answer your questions. You also can highlight key ideas as well as write in the margins of the text. Highlighting should generally be limited to main ideas in order to reduce the clutter of highlighting everything. Writing in the margins allows you to make quick notes to yourself about key points and or to summarize a dense concept. Doing either of these is a way to wrestle with a text in an active manner which is important for comprehension.

After Reading

After you have read and answered your questions in a text. There are several things left to do.

Determine what did you learn. Write briefly a few notes to yourself about what exactly you learned. This is for you and helps to make sense of all the details in your mind at the moment.

Look at the Resources at the back of the chapter. Many textbooks have several study tools at the back of the chapter. Example this includes an outline of the chapter which is a great summary, discussion questions which help in developing critical thinking skills, and often vocabulary words are here as well. When preparing for an exam this is an excellent resource.

Conclusion

This process is not as much work as it seems. With practice, it can become natural. In addition, you need to modify this so that you can be successful as a reader. The ideas here provide a framework in which you can develop your own style.

Insights into Reading Academic Text

In my experience as a teacher for several years at university, I have noticed how students consistently struggle with reading an academic text. It seemed as those they were able to “read” the words but always lack the ability to understand what the text was about. I’ve thought about this challenge and have been lead to the following conclusions.

  • Many Students believe reading and understanding are the same thing
  • Many Students believe they have no responsibility to think about what they have read
  • Many Students believe there is no reason to connect what they are reading to anything they currently know
  • Many Students see no point to determine how to use or apply what they have read
  • Many Students do not understand how academic writers structure their writing

None of these points apply to everybody. However, it is common for me to ask my students if they read something and they usually that they yes the did read it. However, as I begin to ask questions and to explore the text with them it quickly becomes clear they did not understand anything that they read. This is partially due to the problem that students read passively even though reading is active. The student never thinks of the relevance of the reading to their own life or future career.

In other words, reading is not the problem, rather it is what to do with what they have read. The purpose of studying is to use what you have learned. Few of us have the time, to simply learn for fun. Often, we learn to do something for monetary reasons. In other words, some sort of immediate application is critical to reading success.

Another important aspect of reading comprehension is understanding the structure of academic writing. Textbooks have different subjects but they all have a surprisingly similar structure which often starts with the big picture and zooms down to the details. If students can see the structure it can greatly improve their ability to understand what they are reading.

The Tour Guide Analogy

The analogy that I like to use is that of a tour guide. A tour guide’s job is to show you around a particular place. It could be an entire city or a single tourist attraction it all depends on the level of detail that he or she wants to provide you. Often, at the beginning of a tour, the tour guide will explain the itinerary of the tour. This provides the big picture purpose of the tour group as well as what to expect during the journey.

If the trip is especially detail you may visit several different places. At each place, there will be several places to see at each place that the tour guide will mention. For example, If I go to Thailand for vacation and visit Bangkok there will be several locations within Bangkok that I would visit such as Malls and maybe a museum. It is the tour guide’s job to guide me in the learning experience.

The author of an academic text is like a tour guide. Their job is to show you around the subject they are an expert in. The tour guide has an itinerary while the academic author has a preface/introduction. In the preface, the author explains the purpose of the book, as well as the major themes or “places” they will show you on the tour. The preface also explains who the book is for.

Each chapter in an academic text is one specific place the author wants to show you on the tour. Just as a tour guide may show you a museum in Bangkok so an author will show you one aspect of a subject in a chapter. Furthermore, every chapter has several headings within it. This is the same as me seeing the dinosaur exhibit at the museum or the ancient Thai instruments exhibit. These are the places within the place that you visited.

Tour guide Writer
Expert in their area Exepert in their area
Shows you around the tourist attraction Shows you around a subject area
Explains what you will see today Explains what they will share in a book/chapter
Provides details about the different sights Provides details for the main ideas

We can break this down further about subheadings and more but I think the point is clear. The layout for an academic text is not mysterious but rather highly consistent. Having said this here are some critical ideas to remember when you read.

Statistical Learning

Statistical learning is a discipline that focuses on understanding data. Understanding data can happen through classifying or making a numeric prediction which is called supervised learning or finding patterns in data which is called unsupervised learning,

In this post, we will examine the following

  • History of statistical learning
  • The purpose of statistical learning
  • Statistical learning vs Machine learning

History Of Statistical Learning

The early pioneers of statistical learning focused exclusively on supervised learning. Linear regression was developed in the 19th century by  Legendre and Gauss. In the 1930’s, Fisher created linear discriminant analysis. Logistic regression was created in the 1940’s as an alternative the linear discriminant analysis.

The developments of the late 19th century to the mid 20th century were limited due to the lack of computational power. However, by the 1970’s things began  to change and new algorithms emerged, specifically ones that can handle non-linear relationships

In the 1980’s Friedman and Stone developed classification and regression trees. The term generalized additive models were first used by Hastie and Tibshirani for non-linear generalized models.

Purpose of Statistical Learning

The primary goal of statistical learning is to develop a model of data you currently have to make decisions about the future. In terms of supervised learning with a numeric dependent variable, a teacher may have data on their students and want to predict future academic performance. For a categorical variable, a doctor may use data he has to predict whether someone has cancer or not. In both situations, the goal is to use what one knows to predict what one does not know.

A unique characteristic of supervised learning is that the purpose can be to predict future values or to explain the relationship between the dependent variable and another independent variable(s). Generally, data science is much more focused on prediction while the social sciences seem more concerned with explanations.

For unsupervised learning, there is no dependent variable. In terms of a practical example, a company may want to use the data they have to determine several unique categories of customers they have. Understanding large groups of customer behavior can allow the company to adjust their marketing strategy to cater to the different needs of their vast clientele.

Statistical Learning vs Machine Learning

The difference between statistical learning and machine learning is so small that for the average person it makes little difference. Generally, although some may disagree, these two terms mean essentially the same thing. Often statisticians speak of statistical learning while computer scientist speak of machine learning

Machine learning is the more popular term as it is easier to conceive of a machine learning rather than statistics learning.

Conclusion

Statistical or machine learning is a major force in the world today. With some much data and so much computing power, the possibilities are endless in terms of what kind of beneficial information can be gleaned. However, all this began with people creating a simple linear model in the 19th century.

Conversational Analysis: Request and Response

Within conversational analysis (CA) it is common to analysis peoples request as well as people’s response to a request in the context of a conversation. In this post, we will look at the categories that these requests and responses commonly fall into.

Request

Requests are a specific type of question in conversational analysis. Request almost always involve some sort of action. Either the person asking the request wants to do something or the speaker wants the listener to do something. As such there are only two categories in which request can be classified and they are…

  • Action request
  • Permission request

Action Request

An action request is made when the speaker wants the listener to do something.

A: Can you turn off the light?

Permission Request

A permission request is made when the speaker wants to perform an action and is seeking approval from the listener.

A: You mind if I turn off the light?

Response to Request

The response to a request can be positive or negative. However, when a response is negative it is often indirect.  As such, there are three categories in which a response to a request can be placed.

  • Accept
  • Reject
  • Evade

Accept

Accepting is to grant permission either for the speaker to do something or that the listener will perform the request.

A: Could you turn the light off?
B: No problem

Reject

Rejecting means that a person states directly that they cannot do something

A: Can you turn the light off?
B: No, I can’t

Evading

Evading is the art of saying “no” indirectly to a request. This is done through giving a reason why something cannot be done rather than directly responding

A: Can you turn the light off?
B: I’m busy with the baby

In the example above, person B never says no. Rather, they provide an excuse for not completing the task.

Conclusion

We all have used these various ways of requesting and responding to request. The benefit of CA is being able to breakdown these conversational pairs and understand what is happening beyond the surface level.

Conversational Analysis: Questions & Responses

Conversational analysis (CA) is the study of social interactions in everyday life. In this post, we will look at how questions and responses are categorized in CA.

Questions

In CA, there are generally three types of questions and they are as follows…

  • Identification question
  • Polarity question
  • Confirmation question

Identification Question

Identification questions are questions that employees one of the five W’s (who, what, where, when, why). The response can be opened or closed-ended. An example is below

Where are the keys?

Polarity Question

A polarity question is a question the calls for a yes/no response.

Can you come to work tomorrow?

Confirmation Question

Similiar to the polarity question, a confirmation question is a question that is seeking to gather support for something the speaker already said.

Didn’t Sam go to the store already?

This question is seeking an affirmative yes.

Responses

There are also several ways in which people respond to a question. Below is a list of common ways.

  • Comply
  • Supply
  • Imply
  • Evade
  • Disclaim

Comply

Complying means give a clear direct answer to a question. Below is an example

A: What time is it?
B: 6:30pm

Supply

Supplying is the act of giving a partial response, that is often irrelevant and fails to answer the question.

A: Is this your dog?
B: Well…I do feed it once in awhile

In the example above, person A asks a clear question. However, person B states what they do for the dog (feed it) rather than indicate if the dog belongs to them. Feeding the dog is irrelevant to ownership.

Imply

Implying is providing information indirectly to answer a question.

A: What time do you want to leave?
B: Not too late

The response from person B does not indicate any sort of specific time to leave. This leaves it up to person A to determine what is meant by “too late.”

Disclaim

Disclaiming is the person stating they do not n]know the answer.

A: Where are the keys?
B: I don’t know

Evade

Evading is the act of answering with really answering the question

A: Where is the car
B: David needed to go shopping

In the example above, person B never states where the car is. Rather, they share what someone is doing with the car. By doing this, the speaker never shares where the car is.

Conclusions

The interaction of a question and response can be interesting if it is examined more closely from a sociolinguistic perspective. The categories provided here can support the deeper analysis of conversation.

Conversational Analysis

Conversational analysis is a tool used by sociolinguist to examine dialog between two or more people. The analysis can include such aspects as social factors, social dimensions, and other characteristics.

One unique tool in conversational analysis identifying adjacency pairs. Adjacency pairs are two-part utterances in which the second speaker is replying to something the first speaker said. In this post, we will look at the following examples of adjacency pairs.

  • Request-agreement
  • Question-Answer
  • Assessment-Agreement
  • Greeting-Greeting
  • Compliment-Acceptance
  • Conversational Concluder
  • Complaint-Apology
  • Blame-Denial
  • Threat-Counterthreat
  • Warning-Acknowledgement
  • Offer-Acceptance

Request-Agreement

Request involves asking someone to do something and agreement indicates that the person will do it. Below is an example

A: Could you open the window?
B: No problem

Question-Answer

One person request information from another. THis is different from request agreement because there is no need to agree. Below is an example

A: Where are you from?
B: I am from Laos

Assessment-Agreement

Assessment seeks an opinion from someone and agreement is a positive position on the subject. The example is below

A: Do you like the food?
B: Yeah, it taste great!

Greeting-Greeting

Two people say hello to one another.

A: Hello
B: Hello

Compliment-Acceptance

One person commends something about the other who shows appreciation for the comment.

A: I really like your shoes
B: Thank you

Conversational Concluder

This is a comment that singles the end of a conversation.

A: Goodbye
B: See you later

Complaint-Apology

One person indicates they are not happy with something and the other person express regret over this.

A: The food is too spicy
B: We’re so sorry

Blame-Denial

One person accuses another who tries to defend himself.

A: You lost the phone?
B: No I didn’t!

Threat-Counterthreat

Two people mutually resist each other.

A: Sit down or I will call your parents!
B: Make me

Warning-Acknowledgement

One person issues a threat or danger and the other indicates they understand

A: Look both ways before crossing the street
B: No problem

Offer-Acceptance

One person gives something and the other person shows appreciation

A: Here’s the money
B: Thank you so much

Conclusion

These kinds of conversational pairs appear whenever people talk. For the average person, this is not important. However, when trying to look at the context of a conversation tot understanding what is affecting the way people are speaking understanding and identifying adjacency pairs can be useful.

The Structure of Academic Writing

“The book is boring.” This is a common complaint many lecturers receive from students about the assigned reading in a class. Although this is discouraging to hear it is usually a cry for help. What the student is really saying is that they cannot understand what they are reading. Yes, the read it but they didn’t get it.

The missing ingredient for students to appreciate academic reading is to understand the structure of academic writing. Lecturers forget that students are not scholars and thus do not quite understand how scholars organize their writing. If students knew this they would no longer be students. Therefore, lecturers need to help students not only understand the ideas of a book but the actual structure of how those ideas are framed in a textbook.

This post will try to explain the structure of academic writing in a general sense.

How it Works

Below is a brief outline of a common structure for an academic textbook.

  • Preface
    • Purpose of the book
    • Big themes of the book (chapters)
  • Chapter
    • Objectives/headings provide themes of the chapter
  • Headings
    • Provides theme of a section of a chapter

Here is what I consider to be a major secret of writing. The structure is highly redundant but at different levels of abstraction. The preface, chapter, and headings of a book are all the same in terms of purpose but at different levels of scope. The preface is the biggest picture you can get of the text. It’s similar to the map of a country. The chapter zooms in somewhat and is similar to the map of a city. Lastly, the headings within a chapter are similar to have a neighborhood map of a city.

The point is that academic writing is highly structured and organized. Students often think a text is boring. However, when they see the structure, they may not fall in love with academics but at least they will understand what the author is trying to say. A student must see the structure in order to appreciate the details.

Another way to look at this is as follows.

  • The paragraphs of a heading support the heading
  • The headings of a chapter support the chapter
  • The chapters of a book support the title of the book

A book is like a body, you have cells, you have tissues, and you have organs. Each is an abstraction of a higher level. Cells combine to make tissue, tissues combine to make organs, etc. This structure is how academic writing takes place.

The goal of academic writing is not to be entertaining. That role is normally set aside for fiction writing. Since most students enjoy entertainment they expect academic writing to use the same formula of fun. However, few authors place fun as one of the purposes in their preface. This yet another disconnect between students and textbooks.

Conclusion

Academic writing is repetitive in terms of its structure. Each sub-section supports a higher section in the book. This repetitive structure is probably one aspect of academic writing students find so boring. However, this repetitive nature makes the write highly efficient in terms of understanding giving that the reader is aware of this.

Understanding the Preface of a Textbook

A major problem students have in school is understanding what they read. However, the problem often is not reading in itself. By this I mean the student know what they read but they do not know what it means. In other words, they will read the text but cannot explain what the text was about.

There are several practical things a student can do to overcome this problem without having to make significant changes to their study habits. Some of the strategies that they can use involve looking at the structure of how the writing is developed. Examples of this include the following.

  • Reading the preface
  • Reading the chapter titles
  • Reading the chapter objectives
  • Reading the headings in the chapters
  • Make some questions
  • Now read & answer the questions

In this post, we will look at the benefits of reading the preface to a book.

Reading the Preface

When students are assigned reading they often skip straight to page one and start reading. This means they have no idea what the text is about or even what the chapter will be about. This is the same as jumping in your car to drive somewhere without directions. You might get there eventually but often you just end up lost.

One of the first things a student should do is read the preface of a book. The preface gives you some of the following information

  • Information about the author
  • The purpose of the book
  • The audience of the book
  • The major themes of the text
  • Assumptions

Knowing the purpose of the text is beneficial to understanding the author’s viewpoint. This is often more important in graduate studies than in undergrad.

Knowing the main themes of the book helps from a psychological perspective as well. These themes serve as mental hooks in your mind in which you can hang the details of the chapters that you will read. It is critical to see the overview and big picture of the text so that you have a framework in which to place the ideas of the chapters you will read.

Many books do not have a preface. Instead what they often do is make chapter one the “introduction” and include all the aspects of the preface in the first chapter. Both strategies are fine. However, it is common for teachers to skip the introduction chapter in order to get straight to the “content.” This is fast but can inhibit understanding of the text.

There are also usually an explanation of assumptions. The assumptions serve to tell the reader what they should already know as well as the biases of the author. This is useful as it communicates the position the author takes from the outset with the readers trying to infer this.

Conclusion

The preface serves the purpose of introducing the reader to the text. One of the goals if the preface is to convince the reader why they should read the book. It provides the big picture of the text, shares about the author, and indicates who the book is for, as well as sharing the author’s viewpoint.

Understanding Academic Text

Understanding academic text is possible through making some minor adjustment to one’s reading style. In this post, we will look at the following ideas for improving academic reading comprehension.

  • Reading the chapter titles
  • Reading the chapter objectives
  • Reading the headings in the chapters
  • Examine the Visuals
  • Make some questions
  • Now read & answer the questions

Read the Chapter Titles

You read the chapter title for the same reason as the preface. It gives you the big picture from which you develop a framework for placing the ideas of the author. I am always amazed how many times I ask my students what the title of the chapter is and they have no clue. This is because they were so determined to read that they never set things in place to understand.

For ESL readers, it is critical that they know the meaning of every word in the title. Again this has to do with the importance of the title for shaping the direction of the reading. If the student gets lost in the details this is where teaching support is there for. However, if they have no idea what the chapter is about there is little even the be3st teacher can do.

Read Chapter Objectives

The objectives of a chapter are a promise of what the author will write about. The student needs to know what the promises are so they know what to expect. This is similar to driving somewhere and expecting to see certain landmarks along the way. When you see these landmarks you know you are getting close to the destination.

The objectives provided the big picture of the chapter in a way that the preface provides the big picture of the entire book. Again, it is common for students to skip this aspect of reading comprehension.

Read the Chapter Headings

By now you probably know why to read the chapter headings. If not, it is because the chapter headings tell the student what to expect in a particular section of the chapter. They serve as a local landmark or a localized purpose.

For an extremely efficient (or perhaps lazy) writer, the objectives and the headings of a chapter will be exactly the same with perhaps slight rewording. This is extremely beneficial for readers because not only do they see the objectives at the beginning but the see them stated again as headings in the chapter.

Examine the Visuals

Visuals are used to illustrate ideas in the text. For now, the student simply wants to glance at them. Being familiar with the visuals now will be useful when the student wants to understand them when reading.

When looking at a visual, here are some things to look for

  • Title
  • author
  • date
  • what’s being measured
  • scale (units of measurement)

For an initial superficial glance, this is more than enough

Make Questions, Read, and Answer 

After examining the text, the student should have questions about what the text is about. Now they should write down what they want to know after examining the various characteristics of the chapter and then they begin to read so they can answer their questions

Examine End of the Chapter Tools

After reading the chapter, many authors provide some sort of study tools at the end. I find it most useful to read the chapter before looking too closely at this information. The reason for this is that the summary and questions at the end indicate what the author thinks is important about the chapter. It’s hard to appreciate this if you did not read the chapter yet.

Knowing what is happening at the end of the chapter helps in reinforcing what you read. You can quiz yourself about the information and use this information to prepare for any examines.

Conclusion

Previewing a chapter is a strategy for understanding a chapter. The ideas a student reads about must have a framework in which the pieces can fit. This framework can be developed through examining the chapter before reading it in detail.

Linear Regression vs Bayesian Regression

In this post, we are going to look at Bayesian regression. In particular, we will compare the results of ordinary least squares regression with Bayesian regression.

Bayesian Statistics

Bayesian statistics involves the use of probabilities rather than frequencies when addressing uncertainty. This allows you to determine the distribution of the model parameters and not only the values. This is done through averaging over the model parameters through marginalizing the joint probability distribution.

Linear Regression

We will now develop our two models. The first model will be a normal regression and the second a Bayesian model. We will be looking at factors that affect the tax rate of homes in the “Hedonic” dataset in the “Ecdat” package. We will load our packages and partition our data. Below is some initial code

library(ISLR);library(caret);library(arm);library(Ecdat);library(gridExtra)
data("Hedonic")
inTrain<-createDataPartition(y=Hedonic$tax,p=0.7, list=FALSE)
trainingset <- Hedonic[inTrain, ]
testingset <- Hedonic[-inTrain, ]
str(Hedonic)
## 'data.frame':    506 obs. of  15 variables:
##  $ mv     : num  10.09 9.98 10.45 10.42 10.5 ...
##  $ crim   : num  0.00632 0.02731 0.0273 0.03237 0.06905 ...
##  $ zn     : num  18 0 0 0 0 0 12.5 12.5 12.5 12.5 ...
##  $ indus  : num  2.31 7.07 7.07 2.18 2.18 ...
##  $ chas   : Factor w/ 2 levels "no","yes": 1 1 1 1 1 1 1 1 1 1 ...
##  $ nox    : num  28.9 22 22 21 21 ...
##  $ rm     : num  43.2 41.2 51.6 49 51.1 ...
##  $ age    : num  65.2 78.9 61.1 45.8 54.2 ...
##  $ dis    : num  1.41 1.6 1.6 1.8 1.8 ...
##  $ rad    : num  0 0.693 0.693 1.099 1.099 ...
##  $ tax    : int  296 242 242 222 222 222 311 311 311 311 ...
##  $ ptratio: num  15.3 17.8 17.8 18.7 18.7 ...
##  $ blacks : num  0.397 0.397 0.393 0.395 0.397 ...
##  $ lstat  : num  -3 -2.39 -3.21 -3.53 -2.93 ...
##  $ townid : int  1 2 2 3 3 3 4 4 4 4 ...

We will now create our regression model

ols.reg<-lm(tax~.,trainingset)
summary(ols.reg)
## 
## Call:
## lm(formula = tax ~ ., data = trainingset)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -180.898  -35.276    2.731   33.574  200.308 
## 
## Coefficients:
##             Estimate Std. Error t value Pr(>|t|)    
## (Intercept) 305.1928   192.3024   1.587  0.11343    
## mv          -41.8746    18.8490  -2.222  0.02697 *  
## crim          0.3068     0.6068   0.506  0.61339    
## zn            1.3278     0.2006   6.618 1.42e-10 ***
## indus         7.0685     0.8786   8.045 1.44e-14 ***
## chasyes     -17.0506    15.1883  -1.123  0.26239    
## nox           0.7005     0.4797   1.460  0.14518    
## rm           -0.1840     0.5875  -0.313  0.75431    
## age           0.3054     0.2265   1.349  0.17831    
## dis          -7.4484    14.4654  -0.515  0.60695    
## rad          98.9580     6.0964  16.232  < 2e-16 ***
## ptratio       6.8961     2.1657   3.184  0.00158 ** 
## blacks      -29.6389    45.0043  -0.659  0.51061    
## lstat       -18.6637    12.4674  -1.497  0.13532    
## townid        1.1142     0.1649   6.758 6.07e-11 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 63.72 on 341 degrees of freedom
## Multiple R-squared:  0.8653, Adjusted R-squared:  0.8597 
## F-statistic: 156.4 on 14 and 341 DF,  p-value: < 2.2e-16

The model does a reasonable job. Next, we will do our prediction and compare the results with the test set using correlation, summary statistics, and the mean absolute error. In the code below, we use the “predict.lm” function and include the arguments “interval” for the prediction as well as “se.fit” for the standard error

ols.regTest<-predict.lm(ols.reg,testingset,interval = 'prediction',se.fit = T)

Below is the code for the correlation, summary stats, and mean absolute error. For MAE, we need to create a function.

cor(testingset$tax,ols.regTest$fit[,1])
## [1] 0.9313795
summary(ols.regTest$fit[,1])
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   144.7   288.3   347.6   399.4   518.4   684.1
summary(trainingset$tax)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   188.0   279.0   330.0   410.4   666.0   711.0
MAE<-function(actual, predicted){
        mean(abs(actual-predicted))
}
MAE(ols.regTest$fit[,1], testingset$tax)
## [1] 41.07212

The correlation is excellent. The summary stats are similar and the error is not unreasonable. Below is a plot of the actual and predicted values

We now need to combine some data into one dataframe. In particular, we need the following actual dependent variable results predicted dependent variable results The upper confidence value of the prediction THe lower confidence value of the prediction

The code is below

yout.ols <- as.data.frame(cbind(testingset$tax,ols.regTest$fit))
ols.upr <- yout.ols$upr
ols.lwr <- yout.ols$lwr

We can now plot this

p.ols <- ggplot(data = yout.ols, aes(x = testingset$tax, y = ols.regTest$fit[,1])) + geom_point() + ggtitle("Ordinary Regression") + labs(x = "Actual", y = "Predicted")
p.ols + geom_errorbar(ymin = ols.lwr, ymax = ols.upr)

1.png

You can see the strong linear relationship. However, the confidence intervals are rather wide. Let’s see how Bayes does.

Bayes Regression

Bayes regression uses the “bayesglm” function from the “arm” package. We need to set the family to “gaussian” and the link to “identity”. In addition, we have to set the “prior.df” (prior degrees of freedom) to infinity as this indicates we want a normal distribution

bayes.reg<-bayesglm(tax~.,family=gaussian(link=identity),trainingset,prior.df = Inf)
bayes.regTest<-predict.glm(bayes.reg,newdata = testingset,se.fit = T)
cor(testingset$tax,bayes.regTest$fit)
## [1] 0.9313793
summary(bayes.regTest$fit)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   144.7   288.3   347.5   399.4   518.4   684.1
summary(trainingset$tax)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   188.0   279.0   330.0   410.4   666.0   711.0
MAE(bayes.regTest$fit, testingset$tax)
## [1] 41.07352

The numbers are essentially the same. This leads to the question of what is the benefit of Bayesian regression? The answer is in the confidence intervals. Next, we will calculate the confidence intervals for the Bayesian model.

yout.bayes <- as.data.frame(cbind(testingset$tax,bayes.regTest$fit))
names(yout.bayes) <- c("tax", "fit")
critval <- 1.96 #approx for 95% CI
bayes.upr <- bayes.regTest$fit + critval * bayes.regTest$se.fit
bayes.lwr <- bayes.regTest$fit - critval * bayes.regTest$se.fit

We now create our Bayesian regression plot.

p.bayes <- ggplot(data = yout.bayes, aes(x = yout.bayes$tax, y = yout.bayes$fit)) + geom_point() + ggtitle("Bayesian Regression Prediction") + labs(x = "Actual", y = "Predicted")

Lastly, we display both plots as a comparison.

ols.plot <-  p.ols + geom_errorbar(ymin = ols.lwr, ymax = ols.upr)
bayes.plot <-  p.bayes + geom_errorbar(ymin = bayes.lwr, ymax = bayes.upr)
grid.arrange(ols.plot,bayes.plot,ncol=2)

1

As you can see, the Bayesian approach gives much more compact confidence intervals. This is because the Bayesian approach a distribution of parameters is calculated from a posterior distribution. These values are then averaged to get the final prediction that appears on the plot. This reduces the variance and strengthens the confidence we can have in each individual example.

Review of “Usborne World of Animals”

The Usborne World of Animals was written by Susanna Davidson and Mike Unwin (pp. 128).

The Summary

This book is about animals and how they live in the world. The book has ten sections. The first section covers topics about how animals live in general. Some of the topics in this section include how animals move, eat, smell, taste, touch, hide, etc. The next 8 sections

The next 8 sections cover different animals in different regions of the world. Examples include Toucans in South America, Bears in North America, Gorillas in Africa, Otters in Europe, Panda Bears in Asia, Kangaroos in Australia, and even Elephant Seals in Antartica.

The Good

This book is full of rich photographs and even illustrations that provide additional learning. The photos depict animals in daily life such as a tiger running, polar bears playing, anteaters searching for food, bats sleeping, monkeys jumping, etc. Children will enjoy the pictures tremendously.

The text is fairly readable. The font is normally large with smaller text being of less importance. There is even a little geography mixed as the book organized the animals based on the region they are from. At the beginning of the section is a map showing where on the continent the animals were from.

The Bad

There is little to criticize about this book. One minor problem is the maps are drawn way out of scale. Asia, in particular, looks really strange. Of course, this is not a geography book but it is distracting somewhat in the learning experience.

Another small complaint could be the superficial nature of the text. There are more animals than there is time to really go deeply into. Again, for an expert this m ay be troublesome but this may not be much of a problem for the typical child.

The Recommendation

This text is 5/5 stars. As a teacher, you can use it for reading to your students or add it to your library for personal reading. The photos and colors will provide a vided learning experience for students for years to come.

Common Task in Machine Learning

Machine learning is used for a variety of task today with a multitude of algorithms that can each do one or more of these tasks well. In this post, we will look at some of the most common tasks that machine learning algorithms perform. In particular, we will look at the following task.

  1. Regression
  2. Classification
  3. Forecasting
  4. Clustering
  5. Association rules
  6. Dimension reduction

Numbers 1-3 are examples of supervised learning, which is learning that involves a dependent variable. Numbers 4-6 are unsupervised which is learning that does not involve a clearly labeled dependent variable.

Regression

Regression involves understanding the relationship between a continuous dependent variable and categorical and continuous independent variables. Understanding this relationship allows for numeric prediction of the dependent continuous variable.

Example algorithms for regression include linear regression, numeric prediction random forest as well as support vector machines and artificial neural networks.

Classification

Classification involves the use of a categorical dependent variable with continuous and or categorical independent variables. The purpose is to classify examples into the groups in the dependent variable.

Examples of this are logisitic regression as well as all the algorithms mentioned in regression. Many algorithms can do both regression and classification.

Forecasting

Forecasting is similar to regression. However, the difference is that the data is a time series. The goal remains the same of predicting future outcomes based on current available data. As such, a slightly different approach is needed because of the type of data involved.

Common algorithms for forecasting is ARIMA even artificial neural networks.

Clustering

Clustering involves grouping together items that are similar in a dataset. This is done by detecting patterns in the data. The problem is that the number of clusters needed is usually no known in advanced which leads to a trial and error approach if there is no other theoretical support.

Common clustering algorithms include k-means and hierarchical clustering. Latent Dirichlet allocation is used often in text mining applications.

Association Rules

Associations rules find items that occur together in a dataset. A common application of association rules is market basket analysis.

Common algorithms include Apriori and frequent pattern matching algorithm.

Dimension Reduction

Dimension reduction involves combining several redundant features into one or more components that capture the majority of the variance. Reducing the number of features can increase the speed of the computation as well as reduce the risk of overfitting.

In machine learning, principal component analysis is often used for dimension reduction. However, factor analysis is sometimes used as well.

Conclusion

In machine learning, there is always an appropriate tool for the job. This post provided insight into the main task of machine learning as well as the algorithm for the situation.

Terms Related to Language

This post will examine different uses of the word language. There are several different ways that this word can be defined. We will look at the following terms for language.

  • Vernacular
  • Standard
  • National
  • Official
  • Lingua Franca

Vernacular Language

The term vernacular language can mean many different things. It can mean a language that is not standardized or a language that is not the standard language of a nation. Generally, a vernacular language is a language that lacks official status in a country.

Standard Language

A standard language is a language that has been codified. By this, it is meant that the language has dictionaries and other grammatical sources that describe and even prescribe the use of the language.

Most languages have experienced codification. However, codification is just one part of being a standard language. A language must also be perceived of as prestigious and serve a high function.

By prestigious it is meant that the language has influence in a community. For example, Japanese is a prestigious language in Japan. By high function, it is meant that the language is used in official settings such as government, business, etc., which Japanese is used for.

National Language

A national language is a language used for political and cultural reasons to unite a people. Many countries that have a huge number of languages and ethnic groups will select one language as a way to forge an identity. For example, in the Philippines, the national language is Tagalog even though hundreds of other languages are spoken.

In Myanmar, Burmese is the national language even though dozens of other languages are spoken. The selection of the language is political motivate with the dominant group imposing their language on others.

Official Language

An official language is the language of government business. Many former colonized nations will still use an official language that comes from the people who colonized them. This is especially true in African countries such as Ivory Coast and Chad which use French as their official language despite having other indigenous languages available.

Lingua Franca

A lingua franca is a language that serves as a vehicle of communication between two language groups whose mother tongues are different. For example, English is often the de facto lingua franca of people who do not speak the same language.

Multiple Categories

A language can fit into more than one of the definitions above. For example, English is a vernacular language in many countries such as Thailand and Malaysia. However, English is not considered a vernacular language in the United States.

To make things more confusing. English is the language of the United States but it is neither the National or Official Language as this has never been legislated. Yet English is a standard language as it has been codified and meets the other criteria for standardization.

Currently, English is viewed by many as an international Lingua Franca with a strong influence on the world today.

Lastly, a language can be in more than one category. Thai is the official, national, and standard language of Thailand.

Conclusion

Language is a term that is used that can also have many meanings. In this post, we looked at how there are different ways to see this word.

Review of “Tut’s Mummy: Lost…and Found”

This post is a review of the book Tut’s Mummy: Lost…and Found by Judy Donnelly (pp. 48).

The Summary

This book covers burial of King Tut along with the eventual discovery of his body several

centuries later. The illustrator draws the preservation of the body, funeral procession, and the burial of the mummy. Intersperse are actual artifacts from the tomb such as a game board and necklace.

The book then moves forward several centuries and explains the discovery of King Tut by Howard Carter. There are several more pictures of artifacts as well as a diagram of the burial chamber of King Tut

The Good

This is a good informative read for younger children. The illustrations support the text yet the book is still text driven. What I mean by this is that you can’t just look at the pictures to understand the book. The text and illustrations work together.

There are also several photographs from the time of the discovery of King Tut’s tomb. The photos help in establishing the authenticity of the text. In addition, the text moves at a good pace and never gets bog down in boring details.

The Bad

There is little to complain about in this text. It provides additional details about King Tut’s life and burial that are probably missing from a standard history textbook.

The Recommendation

This book deserves 4/5. It provides excellent supplementary material on a specific part of history. The writing style is brisk and the illustrations are excellent. Add this to our library if you work with elementary age children

Code -Switching & Lexical Borrowing

Code-switching involves a speaker changing languages as they talk. This post will explore some of the reasons behind why people code-switch. In addition, we will look at lexical borrowing and its use in communication

Code-Switching

Code-switching is most commonly caused by social factors and social dimensions of pragmatics. By social factors, it is meant the who, what, where, when and why of communication. Social dimensions involve distance, status, formality, emotions, referential traits.

For example, two people from the same ethnicity may briefly switch to their language to say hello to each other before returning to English. The “what” is two people meeting each other and the use of the mother-tongue indicates high intimacy with each other.

The topic of discussion can also lead to code-switching. For example, I have commonly seen students with the same mother-tongue switch to using English when discussion academic subjects. This may be because their academic studies use the English language as a medium of instruction.

Switching can also take place for emotional reasons. For example, a person may switch languages to communicate anger such as a mother switching to the mother-tongue to scold their child.

There is a special type of code-switching called metaphorical switching. This type of switching happens when the speaker switches languages for symbolic reasons. For example, when I person agrees about something they use their mother tongue. However, when they disagree about something they may switch to English. This switching back and forth is to indicate their opinion on a matter without having to express it too directly.

Lexical Borrowing

Lexical borrowing is used when a person takes a word from one language to replace an unknown word in a different language. Code-switching happens at the sentence level whereas lexical borrowing happens at the individual word level.

Borrowing does not always happen because of a poor memory. Another reason for lexical borrowing is that some words do not translate into another language. This forces the speaker to borrow. For example, many langauges do not have a word for computer or internet. Therefore, these words are borrowed when speaking.

Perceptions

Often, people have no idea that the are code-switching or even borrowing. However, those who are conscious of it usually have a negative attitude towards it. The criticism of code-switching often involves complaints of how it destroys both languages. However, it takes a unique mastery of both languages to effectively code-switch or borrowing lexically.

Conclusion

Code-switching and lexical borrowing are characteristics of communication. For those who want to prescribe language, it may be frustrating to watch two languages being mixed together. However, from a descriptive perspective, this is a natural result of language interaction.

Absolute vs Relative Grading

Grading is a concept that almost no two teachers agree upon. Some believe in including effort while others believe only performance should be considered. Some believe in many A’s while others believe A’s should be rare.

In this post, we will look at absolute and relative grading and how these two ideas can be applied in an academic setting.

Absolute Grading

Absolute grading involves the teacher pre-specifying the standards for performance. For example, a common absolute grading scale would be

A = 90-100
B = 80-89
C = 70-79
D = 60-69
F = 0-59

Whatever score the student earns is their grade.  There are no adjustments made to their grade. For example, if everyone gets a score between 90-100 everyone gets an “A” or if everyone gets below 59 everyone gets an “F.” The absolute nature of absolute grading makes it inflexible and constraining for unique situations.

Relative Grading

Relative grading allows for the teacher to interpret the results of an assessment and determine grades based on student performance. One example of this is grading “on the curve.” In this approach, the grades of an assessment are forced to fit a “bell curve” no matter what the distribution is. A hard grade to the curve would look as follows.

A = Top 10% of students
B = Next 25% of students
C = Middle 30% of students
D = Next 25% of students
F = Bottom 10% of students

As such, if the entire class had a score on an exam between 90-100% using relative grading would still create a distribution that is balanced. Whether this is fair or not is another discussion.

Some teachers will divide the class grades by quartiles with a spread from A-D. Others will use the highest grade achieved by an individual student as the A grade and mark other students based on the performance of the best student.

There are times when institutions would set the policy for relative grading. For example, in a graduate school, you may see the following grading scale.

A = top 60%
B = next 30%
C = next 10%
D, F = Should never happen

the philosophy behind this is that in graduate school all the students are excellent so the grades should be better. Earning a “C” is the same as earning an “F.” Earning a “D” or “F” often leads to removal from the program.

Grading Philosophy

There will never be agreement on how to grade. Coming from different backgrounds makes this challenging. For example, some cultures believe that the teacher should prepare the students for exams while others do not. Some cultures believe in self-assessment while others do not. Some cultures believe in a massive summative exam while others do not

In addition, many believe that grades are objective when there is little evidence to support this in academic research. A teacher who thinks students are low performers gives out such grades even if the students are high achievers.

As such, the most reasonable approach is for a school to discuss grading policies and lay out the school’s approach to grading to reduce confusion even if it does not reduce frustration.

Review of “Peoples of the World”

This post is a review of the book Peoples of the World by Roma Trundle (pp. 32).

The Summary

This book exposes the reader to various aspects of culture have they are addressed by many different people groups. Topics that are addressed include money, food, clothing, craft, religion, language, and music.

For each of these cultural topics, several people groups provide examples of how they address this. For example, for the cultural topic of money, different examples of money our given. You get to see the Russian rouble, Malaysian sens, and Greek drachmas. There are even examples what is not traditional view as money in the west such as the use of salt for money as well as bartering.

This pattern of an aspect of culture followed by examples is repeated throughout the book.

The Good

This book provides a great deal of exposure to cultures that most students are not familiar with. The illustrations are adequate. There are also activities every few pages for the students. Examples include how to wear a sarong, sara, turban, how to make wax pictures, as well as how to make a pinata.

The Bad 

There is a lot of small text on the pages. This makes the book unreadable for younger students. In addition, there are no learning tools or support. This leaves it up to the teacher to determine how to scaffold this material for their students. For younger teachers, this can be much more challenging.

The Recommendation

 I give this book 2/5. There is just a lack of “wow” when looking at this text. Nothing was done to make this book stand out from the crowd. It’s worthy of the library but not valuable in terms of teaching and instruction. Let the kids enjoy the pictures and for the more academically incline to actual read it.

Self-Assessment

Generally, education has always focused on some form of external assessor watching the progress of a student. This is by far the standard approach. However, it is not the only way.

An alternative form of assessment is self-assessment. In this approach, the student judges their progress themselves rather than leaning on the judgment of a teacher. In this post, we will look at the pros and cons of self-assessment as well as several ways to incorporate self-assessment into the classroom

Pros and Cons

Some of the advantages of this include the following.

  • Autonomy-The student must be able to ascertain what they are doing well and also wrong
  • Critical thinking skills-This relates to the first bullet. The student must form an opinion about their progress
  • Motivation-Students often are energized by the responsibility of making decisions themselves.

There are also some drawbacks such as the subjectivity of such a form of assessment. However, developing the cognitive skills of self-assessment provide a reasonable tradeoff in many situations.

Types of Self-Assessment

Self-assessment can take one of the following forms

  • Goal setting assessment
  • Assessment of performance
  • General assessment
  • Student-generated test

Goal Setting

Goal setting is the student deciding for themselves what they want to do or achieve in an academic context. The student lays down the criteria and attempts to achieve it. This is an excellent way to boost motivation as many students love to dream even if it is limited to academics.

Assessment of Performance

Performance assessment is the student judging how they did on a specific task. Examples may include assessing their performance of a speech, or essay. Often this is best done with some sort of learning experience that is open ended like the previous examples. IN other words, performance assessment might be meaningless for a multiple-choice quiz since they answer is fixed.

General Assessment

General assessment is assessing one’s performance over time rather than at one specific moment. The student might judge their performance over an entire unit or semester and share their thoughts. This is much more vague in nature but if the student walks away with understanding how to improve it can be beneficial.

Student-Generated Test

Having students generate test items strongly encourages review of course content. The student has to identify what they know and do not know as well as the level of understanding of their peers. This complex metacognitive process always for stronger insights into the content.

Supporting Self-Assessment

As the teacher, it is necessary to consider the following

  1. Clearly, define what needs to be done. This is often best done through giving an example through demonstration of self-reflection.
  2. Consider the format. THe teacher can provide a checklist, surveys, or require students to write a self-assessment. The format depends on the goals as well as the abilities of the students.
  3. Challenge the student’s assessment. Students will often be too harsh or easy on themselves. Having the students explain their position will deepen their critical thinking skills and encourage impartial assessments.

Conclusion

Self-assessment is another potential tool in the classroom. This form of assessment allows students to think and decide where they believe they are in their learning experience. As such, occasional use of this approach is probably beneficial for most students.

Conferencing with Students

Conferences can play a vital role in supporting the growth and improvement of your students. The one-on-one interaction is a priceless use of time for them. In this post, we will look at conferencing and the process for successful use of this idea.

Conferencing

A conference is an opportunity for a teacher and student to discuss one-on-one the students progress in regards to the student’s academic performance. By academic performance, it can mean summative performance or formative.

Conferences can also be used for long term projects such as papers, research, or other more complex assignments.  The length of time does not have to be more than 5-10 minutes in order to provide support. The personal nature of a conference seems to work even in such a short amount of time.

Below are some steps to take when conducting a conference with a student

  1. Explain what is going well
  2. Ask the student if they see any other strengths
  3. Explain what needs to be improve
  4. Ask the student if they see any other problems
  5. Provide suggestions on how to improve weaknesses
  6. Let the student suggest ways to improve
  7. Ask the student if they have any questions

The Good

Begin by sharing what was excellent about the paper. This prepares the student for the bad news. There is almost always something to praise even from the weakest students.

You can also solicit what the student thinks is strong about their paper. This encourages critical thinking as it requires them to form an opinion and provide reasons for it. This also encourages dialog and makes conferences collaborative rather than top-down communication.

Conferences need to be evidence based. This means when something is good you have an example from the paper for the student of what good looks like. THe same applies for bad as well. Concrete examples are what people need to understand and learn.

The Bad

Next, it is time to share the problems with the paper. As the teacher, you point out where improvement is necessary. In addition, you allow the student to share where they think they can do better. Often there is awkward silence but self-reflection is critical to success.

If the student remains silent,  you may elicit a response through asking them questions about their paper that indicates a weakness. Soon the student begins to see the problems for themselves.

The Solution

With problems identified it is important to provide ways to improve. This is where the learning begins. They see what’s wrong and they learn what is right. Naturally, the student can contribute as well to how to improve.

This is also a place where the teacher asks if there are any questions. By this pointing dialoguing has gone on for awhile and questions were probably already asked and answered. However, it is still good to ask one more time in case the student was waiting for whatever reason.

Conclusion

Conferencing is time-consuming but it provides an excellent learning experience for students. It is not necessary for them to be long if there is adequate preparation and there is some sort of structure to the experience.

Review of “The Greek News”

In this post, we will take a look at the book History News: The Greek News by Anton Powell and Philip Steele (pp. 32).

The Summary

This book takes actually historical events from Ancient Greece and reduces them into newspaper style articles. The writing style is similar to anything you would see on CNN, NBC, New York Times, etc. Some of the stories in the book include an article on the anger of Greeks on colonists returning to Greece instead of staying overseas The anger was due to the lack of food in Greece and the frustration of having to support the returning colonist.

Another story is the victories of Alexander the Great and his untimely death in his early thirties. There are also several articles on life in Sparta as well as the Olympic Games. There are also advertisements on several pages just as in a real newspaper. My personal the potty training toilet for small children (pg. 18). I am assuming this book is historically accurate

The Good

The authors truly earn an ‘A’ for creativity. Taking the unknown (Greek History) and combining it with the know (modern day news writing) is an excellent pedagogical tool. Like all newspapers, there are many illustrations. Not with photos of course as they were not invented yet but with hand drawings. 

The stories are interesting and give you a picture of everyday life in Greece. There are interviews with housewives, actors, and even architects.

The Bad

Creativity can also be a curse. I love this approach but it may be confusing to people who cannot juxtapose news articles with ancient Greek history. This is probably especially true with young children as they are unfamiliar with both Ancient Greece and news-style writing.

The writing almost assumes that the reader is Greek. Again this requires a lot of background knowledge prior to using this text. Perhaps at the end of a unit on Greece would be an appropriate time to use this text. You may want to try photocopying a few articles and reading them together as a class.

The Recommendation

This book deserves 4.5/5 stars. It is highly engaging with its use of illustration and the clever use of news style writing. The kids will enjoy the pictures and the unique approach to teaching. In addition, for students, they need to be prepared for this type of learning experience through other forms of exposure to Ancient Greece. In other words, this text is excellent supplementary materials, however, a foundation should be laid in advance of the main points of Ancient Greece to avoid confusion due to the writing style of this text.

Social Dimensions of Language

In sociolinguistics, social dimensions are the characteristics of the context that affect how language is used. Generally, there are four dimensions to the social context that are measured are analyzed through the use of five scales. The four dimension and five scales are as follows.

  • Social distance
  • Status
  • Formality
  • Functional (which includes a referential and affective function)

This post will explore each of these four social dimensions of language.

Social Distance

Social distance is an indicator of how well we know someone that we are talking to.  Many languages have different pronouns and even declensions in their verbs based on how well they know someone.

For example, in English, a person might say “what’s up?” to a friend. However, when speaking to a stranger, regardless of the strangers status, a person may say something such as “How are you?”. The only reason for the change in language use is the lack of intimacy with the stranger as compared to the friend.

Status

Status is related to social ranking. The way we speak to peers is different than how we speak to superiors. Friends are called by their first name while a boss, in some cultures, is always referred to by Mr/Mrs or sir/madam.

The rules for status can be confusing. Frequently we will refer to our parents as mom or dad but never Mr/Mrs. Even though Mr/Mrs is a sign of respect it violates the intimacy of the relationship between a parent and child. As such, often parents would be upset if their children called them Mr/Mrs.

Formality

Formality can be seen as the presence or absences of colloquial/slang in a person’s communication. In a highly formal setting, such as a speech, the language will often lack the more earthy style of speaking. Contractions may disappear, idioms may be reduced, etc. However, when spending time with friends at home a more laid-back manner of speaking will emerge

However, when spending time with friends at home a more laid-back manner of speaking will emerge. One’s accent becomes more promeneint, slang terms are permissiable, etc.

Function (Referential & Affective)

Referential is a measure of the amount of information being shared in a discourse. The use of facts, statistics, directions, etc. Affective relates to the emotional content of communication and indicates how someone feels about the topic.

Often referential and affective functions interrelated such as in the following example.

James is a 45 year-old professor of research who has written several books but is still a complete idiot!

This example above shares a lot of information as it shares the person’s name, job, and accomplishments. However, the emotions of the speaker are highly negative towards James as they call James a “complete idiot.”

Conclusion 

The social dimensions of language are useful to know in order to understand what is affecting how people communicate. The concepts behind the four dimensions impact how we talk without most us knowing why or how. This can be frustrating but also empowering as people will understand why they adjust to various contexts of language use.

Journal Writing

A journal is a log that a student uses to record their thoughts about something. This post will provide examples of journals as well as guidelines for using journals in the classroom.

Types of Journals

There are many different types of journals. Normally, all journals have some sort of dialog happening between the student and the teacher. This allows both parties to get to know each other better.

Normally, journals will have a theme or focus. Examples in TESOL would include journals that focus on grammar, learning strategies, language-learning, or recording feelings. Most journals will focus on one of these to the exclusion of the others.

Guidelines for Using Journals

Journals can be useful if they are properly planned. As such, a teacher should consider the following when using journals.

  1. Provide purpose-Students need to know why they are writing journals. Most students seem to despise reflection and will initially reject this learning experience
  2. Forget grammar-Journals are for writing. Students need to set aside the obsession they have acquired for perfect grammar and focus on developing their thoughts about something. There is a time and place for grammar and that is for summative assessments such as final drafts of research papers.
  3. Explain the grading process-Students need to know what they must demonstrate in order to receive adequate credit.
  4. Provide feedback-Journals are a dialog. As such, the feedback should encourage and or instruct the students.  The feedback should also be provided consistently at scheduled intervals.

Journals take a lot of time to read and provide feedback too. In addition, the handwriting quality of students can vary radically which means that some students journals are unreadable.

Conclusion

Journaling is an experience that allows students to focus on the process of learning rather than the product. This is often neglected in the school experience. Through journals, students are able to focus on the development of ideas without wasting working memory capacity on grammar and syntax. As such, journals can be a powerful in developing critical thinking skills.

Review of “Usborne Time Traveler”

This post is a review of the book Usborne Time Traveler (pp. 130).

The Summary

This is a historical text that takes you on a journey of historical time periods the Knights, Vikings, Romans, and ancient Egypt. An unnamed boy has this “helmet” that allows him to travel to this different periods.

In each period, there is a list of the type of people you will read about as well as a fictitious family. The family is always a wealthy or aristocratic family. For example, in the Knight’s section of the book, you learn about Baron Godfrey’s family. You watch his son Simon become a knight. During the Roman section, we meet Petronius and his family and see his sister Antonia disciplining the children.

Each section of the book depicts daily life and events during that period. For example, during the Viking section, there is preparation for a raid on a village. During the Egyptian section of the book, you get to witness a trip to the market as well as a feast. You also get to witness Baron’s Godfrey’s castle survive a siege from a rival nobleman.

The Good

This book provides examples of the clothing, food, language, and other customs of each culture. The pictures are simple yet provide excellent examples that young children can understand. The fictitious family used in each section helps pedagogically as children can relate to the idea of a family and this knowledge helps them to understand the complex aspects of each time periods culture and ways.

Watching the families interact with their world was always interesting and helped in making this ancient history interesting and relevant. From Caius walking to school with a torch to the funeral of Olaf, it seems as if you are actually there for this small experiences.

The Bad

It’s hard to find any complaints about this book. Both old and young can enjoy this text. The older students can read the text and the younger can focus on the pictures. However, there are some violent scenes in the text at times that some parents may object to.

The Recommendation

This book is absolutely 5/5. It is well-written, has excellent illustrations, and paid attention to concepts of teaching and communication. This book should be any every elementary school’s history teacher’s library.