1. A group of researchers has developed a method that they hypothesize will improve the reading ability of at-risk 1st grade students. They randomly selected nine students to participate in their study. The nine students were administered a reading test, then trained for 10 weeks using the new reading program, and then readministered the reading test. The following data are their scores:
Subject 1st Reading 2nd Reading
Score Score
1 23 19
2 20 19
3 24 21
4 24 24
5 24 22
6 19 17
7 17 15
8 18 16
9 20 18
Which test is most appropriate to use for testing the hypothesis?
Pearson's
Independent t-test
Dependent t-test
Chi-square
0.5 points
QUESTION 2
1. What is the alternative hypothesis for the 1st grade Reading study?
μ Reading1 < μ Reading2 where 1 = pretest and 2 = posttest
μReading1 > μ Reading2 where 1 = pretest and 2 = posttest
μReading1 = μReading2
0.5 points
QUESTION 3
1. What would be the value of your observed test statistic for the reading improvement study?
none of the above
-1.172
-4.603
-0.940
-5.37
0.5 points
QUESTION 4
1. What would be your statistical conclusion using a directional alternative hypothesis test with an alpha = .01?
With the critical value of 1.397, we conclude that we should reject the null hypothesis and conclude that the reading program is effective in significantly increasing reading scores.
With the critical value of 2.90, we conclude that we should reject the null hypothesis and conclude that the reading program is effective in significantly increasing reading scores.
With the critical value of 1.397, we conclude that we should retain the null hypothesis because the observed test statistic indicates that there was actually a decrease in reading scores rather than an increase in reading scores. Thus, because we were conducting a directional test, we would have to conclude that the evidence does not support the hypothesis that the reading program is effective in increasing student reading scores.
With the critical value of 2.90, we conclude that we should retain the null hypothesis because the observed test statistic indicates that there was actually a decrease in reading scores rather than an increase in reading scores. Thus, because we were conducting a directional test, we would have to conclude that the evidence does not support the hypothesis that the reading program is effective in increasing student reading scores.
0.5 points
QUESTION 5
1. Use the following research question and data for questions 5 - 10.
A researcher is examining the effects of a computer-based training program designed to teach alge
a. The researcher randomly selects subjects for two groups. One group receives instruction using the computer-based training program while the other group receives instruction in a traditional classroom setting using standard teaching methods. The researcher wants to see if the two methods differ in their effectiveness. The following scores are from the subjects' final exam.
Computer-based
Traditional
55
56
58
45
51
47
56
46
53
47
52
39
55
47
44
49
What test is most appropriate for these data and hypothesis?
Independent t-test
Pearson's
Chi-square
Dependent t-test
0.5 points
QUESTION 6
1. What is the null hypothesis?
none of the above
0.5 points
QUESTION 7
1. What is the critical value for the hypothesis, using a non-directional test and an alpha of 0.05?
1.753
2.145
2.131
1.761
0.5 points
QUESTION 8
1. What is the observed value for the chosen test statistic?
2.67
2.23
0.24
5.00
0.5 points
QUESTION 9
1. The researcher can conclude that:
Every student who used the computer program scored higher than any student who did not use the program.
Students in the computerized alge
a training group had significantly higher test scores than students who received standard teaching methods.
There is no significant difference in the performance of students receiving the computer training as computer to the students receiving standard teaching methods.
0.5 points
QUESTION 10
1. Compute the effect size for the difference between the Computer-based Alge
a group (treatment) and the Traditional Alge
a group (control) using Smith and Glass's ∆ (refer back to chapter 7 for this formula).
6
0.23
1.07
1.28
0.5 points
QUESTION 11
1. Research Hypothesis: The GPA's of undergraduate students majoring in Chemical Engineering will be significantly lower than the GPA's of undergraduate students majoring in Sociology and the GPA's of undergraduate students majoring in Music. What type of test statistic would be used to investigate the hypothesis?
one-sample z-test
analysis of variance
dependent t-test
chi-square
0.5 points
QUESTION 12
1. The proportion of teachers who take summer courses is greater than the proportion of business persons who take summer courses. What would be the appropriate test statistic for investigating this research hypothesis?
Chi-square
analysis of variance
dependent t-test
one-sample z-test
0.5 points
QUESTION 13
1. A group of researchers hypothesizes that listening to music while studying for an exam influences test scores. They randomly selected 28 subjects and randomly assigned them to one of four groups. All groups studied for a test one hour a day for a week. Group 1 studied without music. Group 2 studied with classical music in the background, group 3 with country, and group 4 with jazz. The following are the final test scores:
Group 1
Group 2
Group 3
Group 4
50
59
60
49
45
57
49
45
42
57
56
45
41
55
55
42
40
56
54
41
39
53
51
39
44
48
46
47
2.
3. What test is most appropriate for this data and hypothesis?
Chi-square
Analysis of Variance
One-Sample z-test
Dependent t-test
0.5 points
QUESTION 14
1. A group of 100 college students and 100 college graduates was asked to reply to the question, "In general, do you enjoy reading a college textbook?" The following are the frequency counts for their responses on the 3-option item.
Usually
Sometimes
Neve
Students
30
25
45
Graduates
50
20
30
2.
3. What is the appropriate test statistic for this type of data?
Dependent t-test
One-sample z-test
Analysis of Variance
Chi-square
0.5 points
QUESTION 15
1. What is the value of the observed test statistic?
8.56
12.99
83.52
5.32
0.5 points
QUESTION 16
1. The critical value that you would use for an alpha level of .10 in the problem comparing college students' and graduates' enjoyment of reading textbooks is:
2.706
.211
4.605
5.991
0.5 points
QUESTION 17
1. The researcher can conclude that:
There is not a relationship between being a cu
ent student or a graduate and enjoying textbook reading.
Students who have graduated read more than cu
ent college students.
There is not enough evidence to make a decision.
There is a difference in the enjoyment of reading textbooks between graduates and cu
ent students.
0.5 points
QUESTION 18
1. A Democratic party representative wants to determine if the proportion of voters for the Democratic, Republican, and Reform candidates differed by gender in a recent election.Two hundred voters were randomly selected for the study. Of the male voters, 40 voted for the Democratic candidate, 40 for the Republican candidate, and 10 for the Reform candidate. The number of female voters voting for Democratic, Republican, and Reform candidates was 60, 30, and 20, respectively.
What test is the most appropriate for these data?
Chi-Square
Dependent t-test
One Sample z-test
Analysis of Variance
0.5 points
QUESTION 19
1. Compute the observed test statistic. Round to two decimal places.
0.5 points
QUESTION 20
1. What would be your research conclusion using an alpha = .05?
A critical value of 3.841 would indicate that we would reject the null hypothesis and conclude that there is a significant relationship between gender and political party affiliation.
A critical value of 9.210 would indicate that we would retain the null hypothesis and conclude that there is not a significant relationship between gender and political party affiliation.
A critical value of 1.386 would indicate that we would reject the null hypothesis and conclude that there is a significant relationship between gender and political party affiliation.
A critical value of 5.99 would indicate that we would reject the null hypothesis and conclude that there is a significant relationship between gender and political party affiliation.