CH3 post-test

A population of scores has a mean of µ = 26, a median of 23, and a mode of 22. What is the most likely shape for the population distribution? A. It cannot be determined from the information given. B. positively skewed C. symmetrical D. negatively skewed

B

A sample of n = 25 scores has M = 20 and s2 = 9. What is the sample standard deviation? A. 9 B. 3 C. 4.5 D. 81

B

What are the values for SS and variance for the following sample of n = 4 scores? Sample: 1, 1, 0, 4 A. SS = 9 and variance = 2.25 B. SS = 9 and variance = 3 C. SS = 18 and variance = 9 D. SS = 18 and variance = 6

B

One item on a questionnaire asks students how many times in a typical week they eat at a fast-food restaurant. The responses for a sample of n = 10 students are summarized in the frequency distribution. What is the best measure of central tendency for these data?X f5 or more 24 33 22 11 10 1 A. mode B. The best measure of central tendency cannot be determined for these data. C. median D. mean

C

What is the value of SS (sum of squared deviations) for the following sample?Sample: 1, 1, 1, 3 A. 12 B. 1 C. 3 D. 0

C

A characteristic, usually a numerical value, that describes a sample is called a ____. A. constant B. variable C. parameter D. statistic

D

Figure 2.1 Frequency on the y-axis Numbers 1-6 on the x-axis Bar graph and the bars are touching What scale of measurement was used to measure the scores in the distribution shown in the accompanying graph? A. cannot be determined B. ordinal C. nominal D. interval or ratio

D

For the following frequency distribution of exam scores, what is the lowest score on the exam?X90-94 85-89 80-84 75-79 70-74 F 3 4 5 2 1 A. x = 74 B. x = 90 C. x = 70 D. cannot be determined

D

Which set of scores has the smallest standard deviation? A. 11, 17, 31, 53 B. 27, 105, 10, 80 C. 5, 11, 42, 22 D. 145, 143, 145, 147

D

For a negatively skewed distribution with a mean of M = 20, what is the most probable value for the median? A. 20 B. less than 20 C. greater than 20 D. It cannot be determined from the information given.

c