Chapter 8

Question 1

T Test for Independent Means

Answer 1

Hypothesis-testing procedure in which there are two separate groups of people tested and in which the population variance is not known

Question 2

Distribution of Differences Between Means

Answer 2

Distribution of differences between means of pairs of samples such that, for each pair of means, one is from one population and the other is from a second population

Question 3

Pooled Estimate of the Population Variance

Answer 3

In a t test for independent means, weighted average of the estimates of the population variance from two samples

Question 4

Weighted Average

Answer 4

Average in which the scores being averaged do not have equal influence on the total, as in figuring the pooled variance estimate in a t test for independent means

Question 5

Variance of a Distribution of Differences Between Means

Answer 5

One of the numbers figured as part of a t test for independent means
It equals the sum of the variances of the distributions of means associated with each of the two samples

Question 6

Standard Deviation of the Distribution of Differences Between Means

Answer 6

In a t test for independent means, square root of the variance of the distribution of differences between means

Question 7

Harmonic Mean

Answer 7

Special average influenced disproportionately by smaller numbers