A quality control engineer is in charge of the manufacture of computer disks. Two different processes can be used to manufacture the disks. He suspects that the Kohler method produces a greater proportion of defects than the Russell method. He samples 150 of the Kohler and 200 of the Russell disks and finds that 27 and 18 of them, respectively, are defective. If Kohler is designated as "Group 1" and Russell is designated as "Group 2," which of the following tests will you use to find out if the Kohler method is worse than the Russell method? A) paired t test B) Friedman rank test C) Z test for difference in proportions D) ç²test for difference in proportions

Question

Quizplus · Accepted Answer

In this scenario, we are comparing the proportions of defective disks produced by two different processes. The appropriate test to use is the Z-test for difference in proportions. The other options, such as paired t test and Friedman rank test, are not suitable in this case. The corresponding statistical test for this situation is Z-test for difference in proportions.

A Quality Control Engineer Is in Charge of the Manufacture