A set of 10 scores has SS = 90.If the scores are a sample,the sample variance is ____ and if the scores are a population,the population variance is ____. A)s² = 9; σ² = 9 B)s² = 9; σ² = 10 C)s² = 10; σ² = 9 D)s² = 10; σ² = 10

Question

Quizplus · Accepted Answer

The sample variance can be calculated as SS/(n-1) where SS is the sum of squared deviations from the mean, and n is the sample size. In this case, SS = 90 and n = 10, so the sample variance is 90/(10-1) = 10.

If the scores are a population, the population variance can be calculated as SS/n, where SS is the sum of squared deviations from the mean, and n is the population size. Since we don't know the population size, we can't calculate the population variance exactly. However, we can make an estimate based on the sample variance. If the sample is representative of the population, we can assume that the sample variance is a good estimate of the population variance. In that case, the population variance would also be 10.

Therefore, the best choice is C, which has matching sample and population variances of 10.

A Set of 10 Scores Has SS = 90