T-Test .)
IV . Because P > .05, we cannot reject H 0 . We do not have strong evidence to back up Booker’s
claim that the books he reads actually average more than 375 pages in length.
The data are paired by individual students, so we need to test the difference scores for the students
rather than the means for each quiz. The differences are given in the following table.
I . Let μ (^) d = the mean of the differences between the scores of students on Quiz 2 and Quiz 1.
H 0 : μ (^) d = 0.
H (^) A : μ (^) d > 0.
II . This is a matched pairs t -test. That is, it is a one-sample t -test for a population mean. We
assume that these are random samples from the populations of all students who took both
quizzes. The significance level is α = 0.05.
A boxplot of the difference scores shows no significant departures from normality, so the
conditions to use the one-sample t- test are present.
III .
(Using the TI-83/84, P -value = tcdf(2.33, 100,9)=0.022 , or you can use STAT TESTS
T-Test .)
IV . Because P < 0.05, we reject the null hypothesis. The data provide evidence at the 0.05 level
that the review was successful at improving student performance on the material.