1. A measure of how scores scatter around the center of a distribution is
a. Variance.
b. Standard deviation.
c. Range.
d. All of the above.
2. Which of the following statements is most true about the relative size of measures of variability?
a. The standard deviation is usually larger than the variance.
b. The variance is usually larger than the standard deviation.
c. The variance and the standard deviation are equal in size.
d. The standard deviation is usually larger than the range.
3. The greater the variability around the mean of a distribution, the larger the
a. Range.
b. Standard deviation.
c. Variance.
d. All of the above.
4. How many standard deviations tend to cover the entire range of scores in a distribution?
a. 2
b. 4
c. 6
d. 8
5. The so-called normal range within which approximately two-thirds of all scores fall is located
a. Within one standard deviation above and below the mean.
b. Between the highest and lowest scores in a distribution.
c. Two standard deviations above the mean.
d. Close to the value of the inter-quartile range.
6. The standard deviation and variance assume
a. Nominal data.
b. Ordinal data.
c. Interval data.
d. A normal distribution.