Friday, March 30, 2012

Mega Million Mania!!!

The Wall Street Journal chimes in...

Is Mega Millions’ $640 Million Jackpot a Good Bet?
The money quote:

" .... plots the expected value of a ticket against the size of the jackpot, and finds that it looks more or less like a bell-curve. That is, up to a certain point, higher jackpots mean higher expected payouts. But after a certain point, the risk of multiple winners overwhelms the higher jackpots, and the expected payout goes down."

Got that?


Bell curves and all that stuff still a confusing thing for you?

Still refer to your Statistics course as "Sadistics?"

No worries gentle reader. Let me spell it out for you as tenderly as I do for my children.

The lottery is a tax on people who are bad a math.

Hah! Bet you thought that was the punchline. The end of the post! Nazzo fast Guido!!!

It may amuse and encourage you to know that the writer of that article is bad at math too.

quoth an VP/scientist at work in an email exchange on this article:
The statement above is wrong. The distribution is TWO DIMENSIONAL. To do the calculation, you have to separate "old money" from "new money". Old money (tickets bought in a prior drawing) will never win, so that money increases the jackpot but doesn't decrease your probability of winning THIS DRAWING. New money, on the other hand, does both. The best possible situation occurs when there is LOTS OF OLD MONEY and VERY LITTLE NEW MONEY. Unfortunately, greed being what it is, this situation never occurs in the real world. When the old money is high, people go nuts and drive the new money very high.

The lottery. It's not rigged. Neither is Vegas. ;^)

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