When testing for differences of means, you can base statistical inference on the
A)Student t distribution in general
B)normal distribution regardless of sample size
C)Student t distribution if the underlying population distribution of Y is normal, the two groups have the same variances, and you use the pooled standard error formula
D)Chi-squared distribution with ( $n _ { w }$ + $n _ { m }$ - 2)degrees of freedom

Question

Quizplus · Accepted Answer

The Student t distribution can be used when the underlying population distribution of Y is normal, the two groups have the same variances, and the pooled standard error formula is used. This is the most appropriate approach for testing differences of means. The normal distribution can only be used when the sample size is large (usually n > 30). The chi-squared distribution is used for testing independence between two categorical variables.

When Testing for Differences of Means, You Can Base Statistical nwn _ { w }nw​

When Testing for Differences of Means, You Can Base Statistical $n _ { w }$