14 Assume that you want to test the claim that the paired sa
14)
Assume that you want to test the claim that the paired sample data come from a population for which the mean difference is d = 0. Compute the value of the t test statistic. Round intermediate calculations to four decimal places as needed and final answers to three decimal places as needed.The following table shows the weights of nine subjects before and after following a particular diet for two months. You wish to test the claim that the diet is effective in helping people lose weight. What is the value of the appropriate test statistic?
| Subject | A | B | C | D | E | F | G | H | I |
| Before | 168 | 180 | 157 | 132 | 202 | 124 | 190 | 210 | 171 |
| After | 152 | 178 | 145 | 125 | 171 | 126 | 180 | 195 | 163 |
Solution
Find difference for each pair then mean and std dev.
Std error = stddev/rt n
Test statistic = difference/std error.
| Subject | A | B | C | D | E | F | G | H | I | |
| Before | 168 | 180 | 157 | 132 | 202 | 124 | 190 | 210 | 171 | |
| After | 152 | 178 | 145 | 125 | 171 | 126 | 180 | 195 | 163 | |
| Diff | 16 | 2 | 12 | 7 | 31 | -2 | 10 | 15 | 8 | 11 |
| Std dev | 9.473648 | |||||||||
| Std error | 2.856412 | |||||||||
| Test statistic | 3.850985 |
