Mathematical Proof

Loyola College's Joseph Ganem crunches bad data.

Will politicians show you charts and graphs that don't tell the whole story? Can real estate agents mislead you with numbers? Can a low-interest credit card actually cost you more?

Yes, yes, and yes.

Joseph Ganem wants to beat them at their own game. "What I am trying to do is get people to think about numbers in a different way," says the associate professor of physics at Loyola College. "I think if people could do that, they would start to make better decisions."

Ganem, whose day job is to study lasers and how to design new ones, recently penned The Two Headed Quarter: How to See Through Deceptive Numbers and Save Money on Everything You Buy. But the 48-year-old scientist also has seen numbers at play every day, and he's grown wary over the years.

He talks about politicians' ability to mislead with numbers, without exactly lying. One candidate says debt is going up. Another insists the deficit is down. Both facts are true: Even a lower deficit still drives higher debt. "That's the beauty of numbers," he said. "You can take the same data and display it in ways that are precise and mathematically true, but that give a very particular picture, the picture you want people to see."

Zero-interest credit cards? Sure, but by the time you pay the hidden transaction fees, you can actually come up owing money. Or the real estate agent's trick of "anchoring": You'll be shown the most expensive houses first. By the time you get to homes just inside in your actual price range, they'll seem surprisingly affordable.

"When you make financial decisions of any kind, you are comparing numbers, and people often are being intentionally directed to compare the wrong numbers," Ganem said. "I used to see the advertisements, I would listen to these sales pitches, and I would be amused. But as time went on, I started to think: This is real, people are being misled."

And if you think Ganem is making a fuss about nothing, look at the global economic turmoil caused by this nation's sub-prime debt crisis—a crisis brought on by people fooled by misleading numbers. 

Issue date: March, 2008