Carmine reads an article that says that male college students study less than female college students. Carmine wonders if this is really so. He asks 20 randomly selected students – 10 males and 10 females – from his coed dorm to record their study times for a period of 4 weeks. Here are the students’ average weekly study times, to the nearest half-hour:
Male Female
13.5 15.5
6.5 10.0
8.0 10.5
14.5 7.0
12.5 13.0
16.0 12.5
12.0 11.0
9.5 8.5
7.0 8.0
11.5 13.0
a. Is the research hypothesis in this study directional or nondirectional?
b. State the research hypothesis.
c. Calculate t and compare it with the tabled critical t at the .05 ? level. Can you reject the null hypothesis?
d. Do you think these samples are representative of all college males and females? To what populations can Carmine rightfully infer the results?