Identify the most appropriate statistic to analyze each of the following studies and explain why you should use the statistical test you have named.
1. An instructor is interested in developing assignments that will discourage plagiarism. In an effort to accomplish her goal, she develops four different assignments and asks 20 of her students to each rank all four assignments on the likelihood of college students plagiarizing on them (1= most likely to plagiarize and 4 = least likely to plagiarize). Are there differences in the rankings of likelihood to cheat on the four assignments?
2. Two clinical evaluators rank the effectiveness of 10 substance abuse programs (1 = most effective). Are their rankings related?
3. Researchers are trying to improve the reaction time of people over 75 years of age with the goal of decreasing automobile accidents in this age group. They randomly assign 20 participants to a control group or a group which practices reaction time exercises on a computer. Both groups use a driving simulator and their reaction time to a car unexpectedly pulling in front of them is measured. Because reaction time is usually a skewed distribution, the reaction times are converted to ranks. Do the ranks for the control and experimental groups differ?