The Odds of Winning Powerball lottery

(9/17/2013) I love this article - when is the best time to buy lottery. But do we follow its advice? Or most lottery buyers simply believe they will win one day? If you don't have time to read the whole article, here is the conclusion:

1. The expected value for the cash-up front Powerball winnings is always negative. It will never make sense to take the money up front, whether you believe the linear model or the polynomial model. 
2.  The expected value for the annuity, however, is break-even when the jackpot exceeds $345 million in the linear participation model and $380 million in the polynomial model. Since the polynomial model seems more accurate at higher jackpots, go with that one. 
3.  Taxes will probably mean that it is never profitable or sensible to play the lottery. So if you do play, try to minimize them. 

This calculation is only part of all analysis needed. The article has more complete analysis.