4 April 2006

Quality control, one chocolate chip at a time

Kyle Barnes (from left, foreground), Patrick Desmond and Jamie Deal extract and count chocolate chips for an experiment in their Business Statistics class.

One Longwood University business class recently learned about quality control in an unconventional way.

Students in Business Statistics counted the chocolate chips in 18-ounce bags of Chips Ahoy! cookies, which used to promise “1,000 chips in every bag” until there was a change in packaging. At one time, Nabisco, the cookie’s maker, ran an advertising campaign that challenged customers to find fewer than 1,000 chips in each bag.

“I do this as an example to illustrate aspects of quality control,” said Roy Creasey, lecturer in management, who teaches the class. “In the spring semester last year, after I read a newspaper article about the University of Arizona doing this, I had another class, Quality Control, conduct this experiment.”

The counting was done in one class period by seven groups of three or four students each, after Creasey had announced the guidelines. “Rule number one: do not eat the cookies!” he said. The students also were told not to break the cookies, to extract the chips by soaking the cookie in water (the water in their plastic containers eventually looked like a brownish soup), and that every piece of chocolate counts as a chip. As they separated and counted chips on paper towels on their tables, they resembled archaeologists sifting through artifacts.

“The students really enjoy this,” Creasey said.  “Sometimes statistics can be boring, since it’s all numbers. This is a practical application, and it shows the importance of statistics in marketing.”

They found an average of about 910 chocolate chips per bag. The range among groups was from 800 to 1,023 chips. Creasey’s earlier class found an average of about 975 chips in each bag.

“There are certain things that can skew the results,” he said. “A cookie could break, which would cause a chip to break. There could be human error in counting. And, one group this time used hot water to melt the cookies, and the cookies started melting and there was no way to get an accurate count. So, I gave them another bag of cookies.”

An observer mentioned that it was a shame to have to waste cookies. “Sometimes we have to do destructive experiments to get the results we want,” said Creasey, who plans to repeat the experiment in the fall. However, he gave the students, all of whom are business majors, a few bags to enjoy.