预测市场也称为预言性的市场，信息市场，决定市场，想法期货，事件衍生工具或虚拟市场) 。是以进行预测为目的而产生的一种投机市场。输赢与某一特定事件(例如马英九先生会胜出下任中华民国总统选举吗?)，或者参数(例如明日的股市升跌)相绑定，从而决定最终能取得的金钱/物质价值。因此，某一特定事件当前的市场价值就等同于此事件会发生的可能性。例如, 人们认为马英九先生胜出下任中华民国总统选举的概率是75%, 此指数的价值会是$75, 如马英九先生真的胜出, 指数价值会升至$100, 代表此事件已100%发生了。预测市场的以上特性, 令其与赌博相比, 庄家不能得到优势。

Prediction markets (also known as predictive markets, information markets, decision markets, idea futures, event derivatives, or virtual markets) are exchange-traded markets created for the purpose of trading the outcome of events. The market prices can indicate what the crowd thinks the probability of the event is. A prediction market contract trades between 0 and 100%. It is a binary option that will expire at the price of 0 or 100%.