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You want to find out if developmental English courses had a positive affect on students' writing skills. You have a sample of 11 students do a writing sample the first day of class and on the last day of class. You want to determine if there is significant gains in writing ability at the 0.05 level.
You believe the population of difference scores is
post-test | pre-test |
---|---|
42.8 | 40.6 |
57.5 | 55.5 |
35.6 | 33 |
51.2 | 48.3 |
55.3 | 53.1 |
43.6 | 41.6 |
42.5 | 40.3 |
59.4 | 56.3 |
61.9 | 58.8 |
48.1 | 45.7 |
41.6 | 39.2 |
Use a 0.05 significance level.
What is the critical value for this test? (Report answer accurate to three decimal places.)
critical value =
What is the test statistic for this sample? (Use the Post - Pre column and report answer accurate to three decimal places.)
test statistic =
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