Not a Prediction Market

Like a prediction market, Metaculus aims to aggregate many people's information, expertise, and predictive power into high-quality forecasts. However, prediction markets generally operate using real or virtual currency, which is used to buy and sell shares in "event occurrence." The idea is that people buy (or sell) shares if they think that the standing prices reflect too low (or high) a probability in that event. Metaculus, in contrast, directly solicits predicted probabilities from its users, then aggregates those probabilities. We believe that this sort of "prediction aggregator" has both advantages and disadvantages relative to a prediction market.

Advantages of Metaculus Over Prediction Markets

Metaculus has several advantages over prediction markets. One is that Metaculus forecasts are scored solely based on accuracy, while prediction markets may be used for other reasons, such as hedging. This means that sometimes prediction markets may be distorted from the true probability by bettors who wish to mitigate their downside risk if an event occurs.

Metaculus Questions Are Not Polls

Opinion polling can be a useful way to gauge the sentiment and changes in a group or culture, but there is often no single "right answer". For example, the Gallup poll "How worried are you about the environment?" does not have a correct answer.

In contrast, Metaculus questions are designed to be objectively resolvable (like in "Will Brent Crude Oil top $140/barrel before May 2022?"), and forecasters are not asked for their preferences, but for their predictions. Unlike in a poll, over many predictions, participants accrue a track record indicating their forecasting accuracy. These track records are incorporated into the Metaculus Prediction. The accuracy of the Metaculus track record itself is tracked here.