Question

You wish to test the following claim (Ha) at a significance level of α 0.005. For the context of this problem. dPostTest - PreTest where the first data set represents a pre-test and the second data set represents a post-test. (Each row represents the pre and post test scores for an individual. Be careful when you enter your data and specify what your 111 and 112 are so that the differences are computed correctly.) You believe the population of difference scores is normally distributed, but you do not know the standard deviation. You obtain the following sample of data pre-testpost-test 77.5 22.2 73.7 55.4 36.1 71.7 74 59 60 60.4 66.5 52.4 41.5 64.9 46 42.5 53.3 43.3 45.6 33.3 67.7 71.7 36 66.2 48.6 99.2 80.4 47.7 55.7 59.4 25.9 72.9 30.5 72.8 18.1 84.1 71.9 What is the test statistic for this sample? test statistic - (Report answer accurate to 4 decimal places.)

Answer 1

The statistical software output for this problem is:

Paired T hypothesis test: D H1 -H2: Mean of the difference between Post Test and Pre Test Hypothesis test results: Difference Mean Std. Err. DF T-Stat P-value Post Test Pre Test 5.7157895 4.3148544 18 1.3246772 0,2019

Hence,

Test statistic = 1.3247

P - value = 0.2019

p - value is greater than a.

Fail to reject the null

Conclusion: Option D is correct.