A decision market is a stock market for ideas. Examples include: tradesports.com, Iowa Electronic Markets, Yahoo Buzz Game. Markets are set up as parimutuels where winners share amount bet. Contracts can be stratified by outcome.

1996 HP sales forecast study:

• 30 managers from various departments, given $50

• At quarter end, highest priced contract was deemed the market estimate.

• Traditional sales estimates had a 13% average error.

• Decision market estimates had a 6% average error.

DARPA tried and failed to predict terrorism with Policy Analysis Market, or PAM.