cognitive bias in marketing

"In his book Priceless, William Poundstone explains what happened when Williams-Sonoma added a $429 breadmaker next to their $279 model: Sales of the cheaper model doubled even though practically nobody bought the $429 machine. Lesson: If you can't sell a product, try putting something nearly identical, but twice as expensive, next to it. It'll make the first product look like a gotta-have-it bargain. One explanation for why this tactic works is that people like stories or justifications. Since it's terribly hard to know the true value of things, we need narratives to explain our decisions to ourselves. Price differences give us a story and a motive: The $279 breadmaker was, like, 40 percent cheaper than the other model — we got a great deal! Good story."  http://lifehacker.com/5925385/how-numbers-affect-your-shopping-habits