Discussion:
Q1 Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At α = .01, is the degree of certainty independent of credits earned? Certainty
Credits Earned Very Uncertain Somewhat Certain Very Certain Row Total
0-9 12 8 3 23
10-59 8 4 10 22
60 or more 1 7 11 19
Col Total 21 19 24 64
Q2 Prof. Green's multiple-choice exam had 50 questions with the distribution of correct answers shown below. Research question: At α = .05, can you reject the hypothesis that Green's exam answers came from a uniform population?
Correct Answer Frequency
A 8
B 8
C 9
D 11
E 14
Total 50
Q3 Final exam scores for a sample of 20 students in a managerial accounting class are shown. (a) At α = .05, is there a difference in the population median scores on the two exams? Make an Excel worksheet for your Wilcoxon signed-rank test calculations and check your work by using MegaStat or a similar computer package. (b) Perform a two-tailed parametric t test for paired two-sample means by using Excel or MegaStat. Do you get the same decision? Accounting
Student Exam 1 Exam 2
1 70 81
2 74 89
3 65 59
4 60 68
5 63 75
6 58 77
7 72 82
8 71 69
9 52 53
10 79 84
11 84 96
12 95 96
13 83 99
14 81 76
15 59 68
16 54 47
17 75 84
18 92 100
19 70 81
20 54 58
Non parametric Exercise
Q4 Below are grade point averages for 25 randomly chosen university business students during a recent semester. Research question: At α = .01, are the median grade point averages the same for students in these four class levels? GPA
Grade Point Averages of 25 Business Students
Freshman (5 students) Sophomore (7 students) Junior (7 students) Senior (6 students)
1.91 3.89 3.01 3.32
2.14 2.02 2.89 2.45
3.47 2.96 3.45 3.81
2.19 3.32 3.67 3.02
2.71 2.29 3.01
2.82 2.98 3.17
3.11 3.26