Learning Check, Sampling Distributions

1. The variance of a distribution of means (sampling distribution) is

a. smaller than the original population variance.
b. the same as the original population variance.
c. greater than the original population variance.
d. unrelated to the original population variance.

2. Dividing the variance of the population by the number of subjects in each sample gives us

a. the standard deviation of the population.
b. the variance of the sampling distribution of means.
c. an estimate of the sample's standard deviation.
d. the average deviation of the distribution of means.

3. In general, the shape of a distribution of means tends to be

a. unimodal, symmetrical.
b. bimodal, symmetrical.
c. unimodal, skewed.
d. rectangular, symmetrical.

4. As the number of subjects in each sample of a skewed distribution gets larger, the distribution of means becomes

a. less and less like the normal curve
b. a better approximation of the normal curve
c. becomes more positively skewed.
d. becomes more negatively skewed.

Answers below

1. a
2. b
3. a
4. b