ADVANCED T-TEST CONCEPTS -
PORTAGE LEARNING CNSL 503 FINAL
EXAM PREP QUESTIONS AND
ANSWERS
1. When conducting an independent samples t-test, what is the primary purpose of the
Levene’s Test?
A. To determine if the sample sizes of the two groups are equal.
B. To assess the assumption of homogeneity of variance between groups.
C. To calculate the effect size using Cohen’s d.
D. To verify if the dependent variable is measured on a nominal scale.
Answer: B
Conceptual Explanation: Levene’s Test checks whether the variances of two populations
are equal, which is a key assumption for the independent samples t-test.
2. In a paired samples t-test with 25 pairs of participants, what are the degrees of freedom
(df)?
A. 49
,B. 48
C. 24
D. 25
Answer: C
Conceptual Explanation: For paired samples, df = n - 1, where n is the number of pairs. 25
- 1 = 24.
3. Which of the following would most likely increase the power of a t-test?
A. Decreasing the alpha level from 0.05 to 0.01.
B. Using a two-tailed test instead of a one-tailed test.
C. Increasing the population variance.
D. Increasing the sample size.
Answer: D
Conceptual Explanation: Increasing sample size reduces standard error, which increases
the likelihood of detecting a true effect (power).
4. What is the relationship between the t-distribution and the normal distribution as the
sample size increases?
A. The t-distribution becomes more skewed.
B. The t-distribution becomes flatter with thicker tails.
, C. The two distributions become mathematically unrelated.
D. The t-distribution approaches the shape of the normal distribution.
Answer: D
Conceptual Explanation: As degrees of freedom increase, the t-distribution converges
toward the standard normal distribution (Z-distribution).
5. A researcher reports t(28) = 2.15, p < .05 for an independent samples t-test. How many
total participants were in the study?
A. 28
B. 29
C. 31
D. 30
Answer: D
Conceptual Explanation: For independent samples, df = N - 2. If df = 28, then N = 30.
6. Which effect size measure is specifically used for t-tests to indicate the magnitude of the
difference in standard deviation units?
A. Pearson’s r
B. Cohen’s d
C. Eta-squared
PORTAGE LEARNING CNSL 503 FINAL
EXAM PREP QUESTIONS AND
ANSWERS
1. When conducting an independent samples t-test, what is the primary purpose of the
Levene’s Test?
A. To determine if the sample sizes of the two groups are equal.
B. To assess the assumption of homogeneity of variance between groups.
C. To calculate the effect size using Cohen’s d.
D. To verify if the dependent variable is measured on a nominal scale.
Answer: B
Conceptual Explanation: Levene’s Test checks whether the variances of two populations
are equal, which is a key assumption for the independent samples t-test.
2. In a paired samples t-test with 25 pairs of participants, what are the degrees of freedom
(df)?
A. 49
,B. 48
C. 24
D. 25
Answer: C
Conceptual Explanation: For paired samples, df = n - 1, where n is the number of pairs. 25
- 1 = 24.
3. Which of the following would most likely increase the power of a t-test?
A. Decreasing the alpha level from 0.05 to 0.01.
B. Using a two-tailed test instead of a one-tailed test.
C. Increasing the population variance.
D. Increasing the sample size.
Answer: D
Conceptual Explanation: Increasing sample size reduces standard error, which increases
the likelihood of detecting a true effect (power).
4. What is the relationship between the t-distribution and the normal distribution as the
sample size increases?
A. The t-distribution becomes more skewed.
B. The t-distribution becomes flatter with thicker tails.
, C. The two distributions become mathematically unrelated.
D. The t-distribution approaches the shape of the normal distribution.
Answer: D
Conceptual Explanation: As degrees of freedom increase, the t-distribution converges
toward the standard normal distribution (Z-distribution).
5. A researcher reports t(28) = 2.15, p < .05 for an independent samples t-test. How many
total participants were in the study?
A. 28
B. 29
C. 31
D. 30
Answer: D
Conceptual Explanation: For independent samples, df = N - 2. If df = 28, then N = 30.
6. Which effect size measure is specifically used for t-tests to indicate the magnitude of the
difference in standard deviation units?
A. Pearson’s r
B. Cohen’s d
C. Eta-squared
