Class: Psychology - Introduction to Statistics

Part I: Research Scenario

A teacher wonders whether there is a difference between men and women students in the amount of time they spend working each week. The teacher gathers the following data from a sample of men and a sample of women students on her campus. It constitutes the hours spent working each work and the data is normally distributed.

Men Women

27 25

19 29

10 23

16 20

22 15

14 19

1. Compute the appropriate t test (SHOW ALL YOUR WORK). Here is some information that will help you save time: SD for men = 6.03; SD for women = 4.91. The sample mean for men is 18 and the mean for women is 21.83. Is this a one-tailed or two-tailed test?
2. Write the H_o and H_a
3. What is t_obt
4. What is t_cv
5. What is df
6. Write your conclusion: Do you have statistical significance? In other words, should you fail to reject the null hypothesis or should you reject the null hypothesis
7. Write a blurb describing the results of your analysis in APA format.
8. Compute Cohen's d for this data
9. Compute the 95% confidence interval for this data

Part II: Now run the analysis in SPSS

1. Your two sample means as indicated by SPSS
2. Your two sample standard deviations as indicated by SPSS
3. Your two Standard Error Mean as indicated by SPSS
4. Your mean difference as indicated by SPSS
5. Your 95% confidence interval for the t: put the lower and upper in brackets (Note that SPSS computes a different confidence interval than I asked you to hand compute)
6. t_obt
7. p
8. Cohen's d
9. Your conclusion: Do you fail to reject the null hypothesis or do you reject the null hypothesis based on the SPSS output