You wish to test the following claim (Ha) at a significance level of = 0.005. For the context of this problem, d =

You wish to test the following claim (Ha) at a significance level of α = 0.005. For the context of this problem, μ d = μ 2 − μ 1 where the first data set represents a pre-test and the second data set represents a post-test. H o : μ d = 0 H a : μ d ≠ 0

You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain pre-test and post-test samples for n = 303 n=303 subjects. The average difference (post - pre) is ¯ d = − 4.2 with a standard deviation of the differences of s d = 31.5 What is the test statistic for this sample?

test statistic = ± 1.641 Incorrect

What is the P-value for this test? For this calculation, use the conservative under-estimate for the degrees of freedom as mentioned in the textbook. (Report answer accurate to four decimal places.) P-value = ± 0.0503 Incorrect