RES/710: Statistical Research Methods And Design I

Wk7 Worksheet: Comparing Groups

Comparing Groups Worksheet

I need help completing the following worksheet below and I have to use my own words not AI generated or any way my instructor knows I'm getting help from a paid source.

This worksheet will help you compare groups using Excel and interpret the results. You'll practice applying a t-test and ANOVA, calculating group means, and using p-values and confidence intervals to support conclusions. Your responses should be clear, complete, and based on the scenario provided.

Scenario

Read the scenario to help you answer questions in this worksheet: A school district is evaluating three different teacher training programs to determine which is most effective at improving student reading scores. After each program, a sample of student scores (out of 100) is collected as follows:

Training A: 78, 82, 85, 79, 81

Training B: 88, 90, 91, 87, 89

Training C: 84, 85, 83, 86, 82

Instructions

Use Excel to perform the analyses and answer each question in the sections below. You'll need to use the built-in Data Analysis Toolpak to run your tests.

Section 1: Understanding the Data

Answer the following questions:

1. What is the independent variable in the scenario?

2. What is the dependent variable?

3. What type of variable is the dependent variable (categorical or numerical)?

Section 2: Descriptive Statistics

Use Excel to calculate descriptive statistics for each group. Enter your results in the table below. Then, answer the following questions.

Statistic	Training A	Training B	Training C
Mean
Median
Standard Deviation

1. Based on the averages, which training program seems most effective? Explain your reasoning.

2. Which group(s) has the most consistent scores (least variability)? How can you tell?

Section 3: Comparing Two Groups with a t-Test

Run an independent samples t-test in Excel (t-Test: Two-Sample Assuming Unequal Variances) comparing Training A and Training B. (You may use the 'assuming unequal variances' option.)

Answer the following questions based on comparing Training A and Training B:

1. What is the p-value?

2. At a significance level of 0.05, is there a statistically significant difference?

3. What does this mean in plain language?

Section 4: Comparing All Groups with ANOVA

Run a one-way ANOVA in Excel for all three groups.

Answer the following:

1. Report the F-statistic and p-value:

2. Based on a significance level of 0.05, what do these results tell you?

3. What can you conclude about the differences among the three training programs?

Section 5: Confidence Intervals

Suppose the 95% confidence interval for Training B is [87.5, 90.5].

Answer the following questions:

1. What does this tell you about the average score for Training B?

2. If this interval does not overlap with the intervals for Training A or C, what does that suggest about the differences between groups?

Section 6: Making a Recommendation

Answer the following questions:

1. If you were a school leader, which training program would you recommend and why? (Answer in 1-2 sentences.)

2. What other factors (besides test scores) should be considered when choosing a training program?

3. What is one limitation of using only statistics to make decisions?