Video

Classroom Insights: Why You Buy What You Buy

Professor Ravi Dhar details recent research in psychology that helps explain how we all make decisions when shopping. When are you impulsive? When do you stick to the stuff on the list? When do you make the good long-term choice? And when do you go for the junk food?

You’re at the grocery store, the kids are being impossible, and you just got a call from the mechanic who has a ton of things he needs to talk to you about—now. You snake through the aisles as usual, yet when you’re finished, your cart is full of extra purchases that you would never buy if you were shopping alone with no distractions. Why?

Or you keep meaning to watch the highbrow indie movie, but at the end of a long day, you find yourself picking the blockbuster with the wooden dialog and the big explosions. What explains this lack of willpower?

Professor Ravi Dhar has some answers. As part of Global Network Week, Dhar, the George Rogers Clark Professor of Management and Marketing, detailed research that seeks to explain the decision-making process. In particular, he described research showing that when the deliberative part of the mind is depleted—in other words, you’re tired—the impulsive mind takes over. It’s no coincidence, he said, that supermarkets are designed with a lot of the junk food towards the end of your shopping. "When it’s the first choice you make, you can resist temptation," he said. "It’s after you made 40 choices in 20 minutes—you’re tired—you just grab the chips that taste good."