Problem 6BSC

use the Wilcoxon rank-sum test.

Taxi-Out Times Listed below are samples of taxi-out times (min) for American Airlines

Flights 19 and 21 (from Data Set 15 in Appendix B). Use the sample data to test the claim that taxi-out times for Flight 19 and Flight 21 have the same median. Use a 0.05 significance level.

Flight 19 15 12 19 18 21 20 13 15 43 18 17 19

Flight 21 13 20 12 17 35 19 22 43 49 45 13 23

Solution 6BSC

Critical values

As the test is a two tailed test and the significance level is 0.05, that is a = 0.05.

Thus the critical values are z = -1.96 , z = 1.96.

Which implies that the critical region is

`

As the value of the test statics doesn’t lie in the critical region ,

So the null hypothesis can’t be rejected..

Step 7 of 7</p>

Interpretation

The median of the taxi-out times of the two flights is same there is no difference.