Discussion Thread: Comparing Groups
Respond to the following short answer questions from Chapter 9 of the Morgan, Leech, Gloeckner, & Barrett textbook:
D7.9.1 (a) Under what conditions would you use a one-sample t test? (b) Provide another possible example of its use from the HSB data.
D7.9.2 In Output 9.2: (a) Are the variances equal or significantly different for the three dependent variables?
(b) List the appropriate t, df, and p (significance level) for each t test as you would in an article.
(c) Which t tests are statistically significant?
(d) Write sentences interpreting the academic track difference between the means of grades in high school and also visualization.
(e) Interpret the 95% confidence interval for these two variables.
(f) Comment on the effect sizes.
D7.9.3 (a) Compare the results of Outputs 9.2 and 9.3.
(b) When would you use the Mann–Whitney U test?
D7.9.4 In Output 9.4: (a) What does the paired samples correlation for mother’s and father’s education mean?
(b) Interpret/explain the results for the t test.
(c) Explain how the correlation and the t test differ in what information they provide.
(d) Describe the results if the r was .90 and the t was zero.
(e) What if r was zero and t was 5.0?
D7.9.5 (a) Compare the results of Output 9.4 with Output 9.5. (b) When would you use the Wilcoxon test?
BOOK:
Morgan, Leech, Gloeckner, & Barrett: IBM SPSS for Introductory Statistics – Sixth Edition