In testing the difference between two population variances are ...

[RRMR]

In testing the difference between two population variances are unknown and not assumed to be equal, two independent samples are drawn from the populations. Which of the following tests is appropriate?
 A. z-test.
  B. pooled variances t-test.
  C. unequal variances t-test.
  D. None of these choices.

Question 2

The quantity is called the pooled variance estimate of the common variance of two unknown but equal population variances. It is the weighted average of the two sample variances, where the weights represent the:
 A. sample variances.
  B. sample standard deviations.
  C. degrees of freedom for each sample.
  D. None of these choices.

[voltaire123]

Answer to Question 1

Analysis:
A. Incorrect. The unequal variances t-test is appropriate.
B. Incorrect. The unequal variances t-test is appropriate.
C. Correct. The unequal variances t-test is appropriate.
D. Incorrect. The unequal variances t-test is appropriate.
ANSWER C

Answer to Question 2

Analysis:
A. Incorrect. The weights represent the degrees of freedom for each sample.
B. Incorrect. The weights represent the degrees of freedom for each sample.
C. Correct. The weights represent the degrees of freedom for each sample.
D. Incorrect. The weights represent the degrees of freedom for each sample.
ANSWER : C