Derek Thompson writes about the JC Penney business model and the psychology of shopping. 

There are two kinds of shoppers, says Brett Gordon, a professor at Columbia Business School. There's the bargain-hunter and the clock-watcher. If the first walks into a store without a bargain, she leaves. But the second customer isn't looking for markdowns. She's looking at her watch. She just wants what she wants, and fast, coupons or no.

What kind of shopper are you?