Why people believe weird things about money

Would you rather earn $50,000 a year while other people make $25,000, or would you rather earn $100,000 a year while other people get $250,000? Assume for the moment that prices of goods and services will stay the same.

Surprisingly -- stunningly, in fact -- research shows that the majority of people select the first option; they would rather make twice as much as others even if that meant earning half as much as they could otherwise have. How irrational is that?

This result is one among thousands of experiments in behavioral economics, neuroeconomics and evolutionary economics conclusively demonstrating that we are every bit as irrational when it comes to money as we are in most other aspects of our lives. In this case, relative social ranking trumps absolute financial status. Here's a related thought experiment. Would you rather be A or B?
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Consider one more experimental example to prove the point: the ultimatum game. You are given $100 to split between yourself and your game partner. Whatever division of the money you propose, if your partner accepts it, you each get to keep your share. If, however, your partner rejects it, neither of you gets any money.

How much should you offer? Why not suggest a $90-$10 split? If your game partner is a rational, self-interested money-maximizer -- the very embodiment of Homo economicus -- he isn't going to turn down a free 10 bucks, is he? He is. Research shows that proposals that offer much less than a $70-$30 split are usually rejected.