1. If other factors are held constant, increasing the number
of scores in the sample will increase the likelihood of rejecting the null
hypothesis.

True

False

2. The distribution of t statistics tends to be flatter and
more spread out than a normal distribution.

True

False

3. In general, the larger the value of the estimated
standard error, the greater the likelihood of rejecting the null hypothesis.

True

False

4. The size of the estimated standard error, SM, is
partially determined by the size of the sample variance.

True

False

5. For a one-tailed test with a = .05 and a sample of n =
25, the critical value for the t statistic is t = 1.711

True

False

6. The general purpose for an interval estimate is to
determine whether or not a treatment has an effect.

True

False

7. If other factors are held constant, increasing the
percentage of confidence from 80% to 90% will increase the width of a confidence
interval.

True

False

8. In general, as sample size increases, the width of a
confidence interval also increases.

True

False

9. Point estimates of the population mean or mean difference
always use t = 0 in the estimation equation.

True

False

10. For an independent-measures study with M1 = 20, M2 = 16
and a pooled variance of 25, the estimated value for Cohen's d = 4/25

True

False

11. The F-max test is used to determine if the two
population means are equal.

True

False

12. For a two-tailed hypothesis with an independent-measures
t statistic using two samples, each with n = 10 scores, the boundaries for the
critical region using a = .05 are t = +/-2.101

True

False

13. If the two samples are the same size, then the pooled
variance will equal the average of the two sample variances.

True

False

14. Two samples, each with n = 4 scores, have a pooled
variance of 32. The estimated standard error for the sample mean difference is
16.

True

False

15. If two samples both have n = 5 and SS = 40, then the
pooled variance is 10.

True

False

16. Two samples, one with n = 6 and one with n = 8, are
being used to estimate the difference between two population means. The t
values for the 95% confidence interval are +/-2.160.

True

False

17. A repeated-measures study requires only 20 participants
to obtain 20 scores in each of the two treatment conditions that are being
compared.

True

False

18. Repeated-measures designs are particularly well-suited
to research questions concerning changes that occur over time.

True

False

19. In a repeated-measures study comparing two treatments
with a sample of n = 15 participants, the researcher measures two scores for
each individual to obtain a total of 30 scores. The repeated-measures
t-statistic for this study has df = 29.

True

False

20. A researcher reports df = 18 for a repeated-measures t
statistic. This research study used a total of n = 19 participants.

True

False

21. A set of n = 16 difference scores has a mean of MD = 4
and a variance of S^2 = 36. Cohen's d for this sample is d = 4/6.

True

False