The main difference between a Z score and a t score is that
A)t scores are used when a study is analyzed with a one-tailed test.
B)t scores are used when the population variance is unknown.
C)t scores are used only when the sample size is greater than 30.
D)t scores are used only when inferences are made about other samples.

Question

Quizplus · Accepted Answer

The main difference between a Z score and a t score is that t scores are used when the population variance is unknown. Z scores are used when the population variance is known. T scores also take into account the sample size, which makes them more suitable for smaller sample sizes.

The Main Difference Between a Z Score and a T