Dr. Z conducts a study in which two groups of participants are compared on a mea
ID: 3394590 • Letter: D
Question
Dr. Z conducts a study in which two groups of participants are compared on a measure of neuroticism. Participants are divided into two groups based on age (under 40 and over 40,) then complete a standardized measure of neuroticism. On the basis of this output for an independent sample t-test, answer the following questions. Assume alpha = .05. NOTE: in order to save space, I have omitted the Levene’s test. Assume that variances are equal.
State the decision you would reach (i.e., reject or fail to reject the null).
In words, interpret the 95% confidence interval.
Group Statistics
age
N
Mean
Std. Deviation
Std. Error Mean
neuroticism
under 40
17
18.40
10.15
2.52
over 40
20
25.42
9.38
3.11
Independent Samples Test
t-test for Equality of Means
t
df
Sig. (2-tailed)
Mean Difference
Std. Error Difference
95% Confidence Interval of the Difference
Lower
Upper
neuroticism
Equal variances assumed
3.11
35
.001
7.02
2.26
3.92
10.12
Group Statistics
age
N
Mean
Std. Deviation
Std. Error Mean
neuroticism
under 40
17
18.40
10.15
2.52
over 40
20
25.42
9.38
3.11
Explanation / Answer
Since the P value is 0.001 which is less than alpha=0.05, thus reject the null hypothesis.
Hence the test is statistically significant.
The 95% Confidence interval is: (3.92,10.12)
The above interval holds the true mean difference with 95% confidence.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.