Saturday, October 12, 2013

How likely are you to win at a casino?

What are the chances that a gambler will win on a single day or over a longer period? ...

Now, thanks to an unprecedented trove of public data detailing the behavior of thousands of Internet gamblers over a two-year period, The Wall Street Journal can provide some answers.

On any given day, the chances of emerging a winner aren't too bad—the gamblers won money on 30% of the days they wagered. But continuing to gamble is a bad bet. Just 11% of players ended up in the black over the full period, and most of those pocketed less than $150.

The skew was even more pronounced when it came to heavy gamblers. Of the top 10% of bettors—those placing the largest number of total wagers over the two years—about 95% ended up losing money, some dropping tens of thousands of dollars. Big losers of more than $5,000 among these heavy gamblers outnumbered big winners by a staggering 128 to 1. ...

To check, the Journal asked Puneet Manchanda of the University of Michigan and Hee Mok Park of the University of Connecticut to analyze a private gambling database to which they have access, detailing two years of play by 18,000 holders of loyalty cards at a Native American casino in the northwestern U.S.

The researchers found similar patterns: Only 13.5% of gamblers ended up winning, versus 11% among Bwin customers, and the ratios of big losers to big winners were similarly large.
--Mark Maremont and Alexandra Berzon, WSJ, on the folly of fighting the law of large numbers