In: Statistics and Probability
Practice Exercise 24: Determining the Appropriate Analysis
For each of the following scenarios, identify the appropriate
analysis. 1. The question is whether verbal reinforcement affects
response rates. Subjects in Group 1 were verbally reinforced every
time they respond to the instructor’s questions. Subjects in Group
2 were not. After 2 weeks, the two groups were compared by gauging
the number of students who raised their hand when questions were
asked. The following data were collected.
Group 1: 13, 15, 12, 17, 14, 14, Group 2: 10, 12, 12, 11, 13,
9
2. A guidance counselor at a high school wants to be best informed
about the universities and colleges that students prefer most
frequently. He glances at the institutions attended by last year’s
graduates and notes that the three closet colleges appear to have
about equal appeal. To test this assumption, he begins asking
students who are planning on postsecondary schooling where they
will apply. His data are as follows:
The technical institute: 22 The community college: 18 The
comprehensive university: 12
3. A biology instructor wishes to know if there is a difference
between performance on a state developed benchmark test and her
comprehensive final examination. To maintain consistency, both test
included the same number of questions (100), and the instructor
used the number of items correct as the grade. The following data
were collected from a sample of 10 students.
Student State exam Biology final
Student State exam Biology final
1 2 3 4 5
56 73 61 85 43
63 74 73 81 57
6 7 8 9 10
60 45 86 79 92
65 51 84 86 94
4. Assume that an educator wants to know how closely time spent
doing homework is related to student grades. Data was collected
from 8 students. Time spent on homework is reported in the number
of hours completed per night, and grades are reported on a 4-point
scale. The following data were collected.
Student | Homework | Grades | Student | Homework | Grades |
1 | .25 | 2.00 | 5 | 1.00 | 2.00 |
2 | .50 | 1.75 | 6 | 1.25 | 2.25 |
3 | .75 | 2.00 | 7 | 1.50 | 2.00 |
4 | 1.00 | 2.50 | 8 | 2.00 | 3.69 |
5. Three groups of students involved in the same curriculum are
obliged to study for 15 minutes, 30 minutes, or 90 minutes a night
for 8 weeks before taking a mathematics test. Scores from 5
students in each group were randomly selected to determine if there
was a difference among the three time groups. Their scores are as
follows:
15 minutes: 43, 39, 55, 56, 73
30 minutes: 55, 58, 66, 79, 82
90 minutes: 61, 66, 85, 86, 91
6. An administrator is interested in determining if the type of
reading curriculum students receive is related to whether they meet
reading standards for their grade. The following data were
collected.
Met Standard | 8 | 5 | 3 |
Did Not Meet | 7 | 13 | 13 |
Standard |
1.
Answer: Independent samples t-test
Explanation: since we are comparing two groups' mean response rates and the population standard deviation is not known, independent samples t-test will be used.
2.
Answer: One sample chi-square test
Explanation: Since we are comparing the observed proportion of students with the expected proportion, the chi-square goodness of fit test should be used.
3.
Answer: Dependent sample t-test
Explanation: Since we are doing repeated measure on same student such that the two exam scores are being measured for each students and being comapred, this is a paired sample study design.
4.
Answer: Correlation Coefficient.
Explanation: the correalation coefficient tells how well the two variables are correlated.
5.
Answer: One way ANOVA analysis
Explanation: Since we are comparing more than two group means, the one way anova analysis is used to test the hypothesis that whether there is a difference among the three group means.
6.
Answer: Chi-square test of Independence
Explanation: Since we want to test whether the two nominal variables are related or not, the chi-square test of independence should be used.