1. A method of conducting a prediction market that obtains prediction market wagers from respective individuals, each wager representing belief of the respective individual as to the outcome of an event, and of extracting a measure of participant utility utilizing the prediction market wagers, the method comprising: receiving data reflecting a first aggregate probability distribution representing a group forecast for the event, including receiving prediction market forecasts from respective individuals, each prediction market forecast reflecting a forecast from the respective individual for the event, and mathematically combining the data representing the prediction market forecasts from the respective individuals to obtain the data representing the first aggregate probability distribution; receiving data reflecting a second probability distribution representing a forecast of a participant for the event, where the participant forecast is placed as a prediction market wager priced in a manner dependent on the first aggregate probability distribution at the time of the prediction market wager by the participant; updating the first aggregate probability distribution responsive to the participant forecast; using a microprocessor based system to calculate a region of difference between a curve representing the second probability distribution and a curve representing the first aggregate probability distribution; determining the measure of participant utility based on the region of difference; and performing at least one of applying the measure of participant utility to a subsequent prediction market computation or formatting the difference data into a browser-readable page for output to indicate a measure of utility of the participant.