A professor is interested in whether there is a difference in counseling students' statistics competency scores among 1) those who have never taken any statistics course, 2) those who have only taken undergraduate statistics course, 3) those who have taken COUN 503, and 4) those who have taken advanced statistic course while working on Ph. D. The professor collects information from the random sample of students and obtains statistics competency scores. The scores are basically distributed.
1) 2) 3) 4)
7 11 13 15
6 11 14 14
8 10 15 15
5 12 12 15
4 13 13 10
4 15 13 15
a. What statistical test should be employed to examine these data?
b. Determine H0 and Ha for this study.
c. Conduct appropriate analysis.
d. Should H0 be rejected? What must the researcher conclude?