A psychologist has developed an aptitude test which consists
A psychologist has developed an aptitude test which consists of a series of mathematical and vocabulary problems. They want to test the hypothesis that the mean test score is 80.
A random sample of 40 people have taken the test and their results recorded:
Download the data
You may find this Student\'s t distribution table useful throughout this question.
a)Calculate the test statistic (t) for the hypothesis test. Give your answer to 4 decimal places.
t =
b)At a level of significance of ? = 0.05, the result of this test is that the null hypothesis is rejectednot rejected.
| 85 | 73 | 73 | 65 | 63 | 68 | 65 | 79 | 92 | 54 |
| 65 | 40 | 62 | 60 | 54 | 65 | 85 | 56 | 58 | 58 |
| 61 | 69 | 76 | 95 | 96 | 78 | 41 | 87 | 66 | 74 |
| 70 | 85 | 91 | 54 | 68 | 85 | 70 | 43 | 51 | 44 |
Solution
(a)
t=(xbar-mu)/(s/vn)
=(68.1-80)/(14.904/sqrt(40))
=-5.0498
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(b)null hypothesis is rejectednot rejected.
| 68.100 | mean Data |
| 14.904 | std. dev. |
| 2.357 | std. error |
| 40 | n |
| 39 | df |
