1. If other factors are held constant, which of the following sets of data would produce the largest value for an independent-measures t statistic?

a. The two samples both have n = 15, with sample variances of 20 and 25.

b. The two samples both have n = 15, with sample variances of 120 and 125.

c. The two samples both have n = 30, with sample variances of 20 and 25.

d. The two samples both have n = 30, with sample variances of 120 and 125. e. Insufficient information to tell

2. If most students did very brilliantly on a test and only a few performed poorly, including a few who did score zero, the distribution of test scores would be:

a. mesokurtic

b. positively skewed

c. leptokurtic

d. Both b) and c) are correct

e. None of the above

Which of the following is true about a 95% confidence interval of the mean of a given sample?

1) There is a 95% chance that the population mean will fall within the upper and lower limits of the confidence interval.

2) 95 out of 100 population means will fall within the limits (i.e., both upper and lower limits) of the confidence interval.

3) There is a .05 probability that sample means will fall within the limits of the confidence interval.

a. 1) only.

b. 1) & 2) only.

c. 2) & 3) only.

d. All of the above.

e. None of the above