-Identify why you choose to perform the statistical test (Signtest, Wilcoxon test, Kruskal-Wallis test).
-Identify the null hypothesis, Ho, and the alternativehypothesis, Ha.
-Determine whether the hypothesis test is left-tailed,right-tailed, or two-tailed.
-Find the critical value(s) and identify the rejectionregion(s).
-Find the appropriate standardized test statistic. Ifconvenient, use technology.
-Decide whether to reject or fail to reject the nullhypothesis.
-Interpret the decision in the context of the originalclaim.
A weight-lifting coach claims that weight-lifters can increasetheir strength by taking vitamin E. To test the theory, the coachrandomly selects 9 athletes and gives them a strength test using abench press. Thirty days later, after regular training supplementedby vitamin E, they are tested again. The results are listed below.Use the Wilcoxon signed-rank test to test the claim that thevitamin E supplement is effective in increasing athletes' strength.Use ? = 0.05.
Athlete | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
Before | 185 | 241 | 251 | 187 | 216 | 210 | 204 | 219 | 183 |
After | 195 | 246 | 251 | 185 | 223 | 225 | 209 | 214 | 188 |
