The Comparison of Teaching Strategies

In any learning environment, there are several different teaching strategies. These strategies (which can be composed of several components such as homework, computer aid, and others) may depend on several factors, such as the teacher's preference, availability of resources, or time constraints. Thus, it is of interest to determine which strategies or components are most effective. The goal of this experiment is to compare several teaching strategies that incorporate two common components (homework assignments (H) and computer tutorials (T)), examining which strategies are most effective. The experiment was conducted on University of Alberta students with a major in Mathematics or Statistics. All 140 student volunteers were randomly assigned to one of four different teaching strategies. The randomization ensured an equal number to each group. The four different groups to consider are the following.

Group 1: C (control group, only lecture notes and discussion)

Group 2: H (control plus weekly homework assignments)

Group 3: T (control plus computer tutorials)

Group 4: HT (control plus weekly homework as well as computer tutorials)

The experiment was conducted over the summer term with the response variable being the student score on the final exam (out of 100) given to students at the end of the term. To ensure equality, the final exam was conducted for all students at the same time in the Pavilion gymnasium. The primary goal of this experiment is to determine if there is a difference in student achievement based on the different teaching methods. If so, which components (homework and computer tutorials) have the greatest impact on learning? All students were taught using the exact same set of course notes.

This dataset is available in theDatalink located in the Lab 4 tab display in the Labs section on eClass. Please import the data into R. (Hint: Students should use "Tabs" as "Field Separator" to import the data set into R Commander.) The data are not to be printed in your submission. The following is a description of the variables in the data file.

Column Variable Name Description of Variable

1 ID ID number assigned to each student

2 Major M = Mathematics, S = Statistics

3 Strategy teaching strategy: C, H, T, HT

4 FX the final exam score (out of 100)

5 FX2 Second final exam score (out of 100) for the control group

1

Use the data to answer questions 1-5.

1. First describe and examine the design.

(a) What is the population of interest? Who are the subjects used in the design? What is the responsevariable?

(b) What is the identifier variable? What is/are the categorical and numerical variable(s) in the data, if any?

(c) Is this an observational study or randomized experiment? Can the results be used to prove that the different teaching strategiescausethe observed differences in midterm scores? Can any inferences be drawn to the population?