Polymarket’s Predictions Prove Over 90% Accurate, New Research Finds

A recent analysis has confirmed that Polymarket accurately predicts events 90% of the time when looking a month ahead, with accuracy rising to 94% just hours before an event occurs.

The study, conducted by New York-based data scientist Alex McCullough, was compiled on a Dune dashboard and examined Polymarket’s historical data. To maintain accuracy, McCullough filtered out markets where probabilities had already settled at extreme levels (above 90% or below 10%) before outcomes were officially determined, ensuring the data remained unbiased.

The Psychology Behind Market Predictions

While Polymarket’s forecasting ability is impressive, McCullough found that the platform tends to slightly overestimate probabilities in many cases. This overestimation could be influenced by factors such as acquiescence bias, herd behavior, and the tendency for traders to favor riskier bets, especially in lower-liquidity markets.

Interestingly, long-term prediction markets often appear more accurate due to the presence of many highly predictable outcomes. McCullough cited a past market that speculated on Gavin Newsom’s chances of becoming U.S. president, which had $54 million in trading volume. Since Newsom was never a serious contender, the market’s correct prediction of his loss artificially boosted Polymarket’s overall accuracy in long-term markets.

Real-Time Accuracy Spikes in Sports Betting

Markets with shorter timeframes, such as sports betting, provide a more precise measure of Polymarket’s predictive capabilities. Unlike political betting—where extreme long shots exist—sports markets are more balanced, making them a truer test of forecasting accuracy. McCullough found that Polymarket’s precision improves significantly as events unfold, often experiencing accuracy spikes just before final outcomes are determined.

The platform’s presence in sports betting has expanded rapidly, with over $4.5 billion wagered on NBA, MLB, Champions League, and Premier League events, according to Polymarket Analytics.

Polymarket’s Political Forecasting: A Look at Canada

Beyond sports, Polymarket’s predictive power is drawing attention in political circles, particularly in Canada. The platform currently shows Mark Carney, the new leader of the Liberal Party, holding a stronger lead over Conservative rival Pierre Poilievre than traditional polling suggests. If Polymarket’s historical accuracy holds true, these forecasts could serve as a valuable alternative to conventional polling data in shaping political expectations.