January  2003

Vol. 5, No. 1

Quality Quiz

Last month we watched as Walker Runn, quality manager for Color in a Can paint manufacturing, put his toe in the water with respect to hypothesis testing. Although he slipped and nearly drowned, he is ready to forge ahead with the next bridge to statistical competency.

This competency was momentarily in doubt when corporate vice president Dan Druff, a statistician himself, visited the plant and challenged Runnís understanding of the t-test.

Luck is with Walker Runn, since the company has just opened a third production line. The following data reflects the three lines.

Production line #1       Production line #2      Production line #3



Walker Runn sees that these are all different from one another, but this time he is ready for the questions that might ensue when Dan Druff examines the data. He learned just last month, after all, how to do a t-test on the difference between means. Now he sees an opportunity to go to town with his new tool, figuring that the answer is simple. He will do a t-test comparing

Line 1 to Line 2

Line 1 to Line 3

Line 2 to Line 3

If any fail the test, he can make his PowerPoint presentation to the vice president and come off as a statistical whiz kid. Will this be the effect?

A) Yes. He may even expect a promotion.

B) No. He may find himself back in the laundry.


Copyright 2003 PQ Systems.

Please direct questions or problems regarding this web site to the Webmaster.