Divide and Conquer

Here's the problem with math. Okay, here's my problem with math. According to an independent survey commissioned by Microsoft, 77 percent of teachers and 73 percent of parents claim math and science are the most difficult homework subjects for students, yet only 36 percent of parents feel capable to help their children.

Microsoft's answer, of course, is more Microsoft software. Specifically, the company has just released its Microsoft Math 3.0, a software packaged designed to help students complete their math and science homework more quickly and easily while teaching important fundamental concepts. I'm all for that, and way back when I first dipped my toe into algebra, trigonometry, calculus, physics, and chemistry, I could have used any and all assistance, digital or otherwise.

"Students often become annoyed when they can’t finish their math homework quickly and waste time searching for help," said Dave Brooks, Education Products Group product manager at Microsoft. "Microsoft Math helps reduce that frustration [bold type added by me] by providing a one-stop shop for help with math and science."

See it is even hard for the smart folks at Microsoft to talk about math without resorting to the word "frustration" in the same sense. (At least Microsoft marketeers aren't trying to say "Math 3.0" as in "Web 2.0". That would be really frustrating.)

But what really is frustrating is that on or about the same day Microsoft cuts loose Math 3.0, researchers at the University of Minnesota published a paper entitled "When Two and Two is Not Equal to Four." Now there's a headline that would even frustrate Math 3.0.

Actually, the complete title of the paper, which was written by Akshay Rao and Haipeng Chen, is When Two and Two is Not Equal to Four: Errors in Processing Multiple Percentage Changes. In it, Rao and Chen examine how consumers treat percentages like whole numbers, resulting in systematic errors in calculation.

"Numerical quantities such as price or product performance are often expressed in percentage form," said Rao. "But when consumers have to deal with more than one percentage at a time, they make errors that can be costly. For instance, if a store offers a 25 percent off sale with an additional 25 percent off for a certain product, people assume they are getting a 50 percent reduction. In reality, they are getting about a 43 percent discount. On a $100 product, they pay $56.25, not $50. This phenomenon becomes even more interesting when a value goes up and then down. Imagine your stock portfolio went up 40 percent last period, and down 30 percent this period. You are not better off by 10 percent. Your portfolio is down 2 percent."

Rao and Chen tested the impact of offering a 20 percent discount and an additional 25 percent discount versus an economically equivalent 40 percent discount in a retail store. The number of purchasers, sales volume, revenue, and profit were all higher when the double discounts were offered.

Here's what would be fun -- a cross-tabulation between the people in Microsoft's survey with the people in Rao and Chen's study. I don't know how it would all add up, but Math 3.0 sales would probably multiply.

Posted by Jon Erickson at 04:14 PM  Permalink