Comment by Hammershaft
9 hours ago
Prediction markets also have very interesting ideas.
https://marginalrevolution.com/marginalrevolution/2025/10/pr...
9 hours ago
Prediction markets also have very interesting ideas.
https://marginalrevolution.com/marginalrevolution/2025/10/pr...
The source is a company that works with Polymarket and sells Polymarket data (as well as Kalshi and other gambling platforms).
The findings are consistent with academic research that these markets are well calibrated.
Could be, you should reference the academic research then.
Marginal revolution has been talking up prediction markets since before they existed. In fact polymarket probably was created after its founder read Cowen's thoughts on prediction markets.
> 12 hour ahead prediction
As the comments on that article rightfully point out, restricting the data analysed to 12 hours before the resolution feels like cherry picking.
Not really.
1. As pointed out in the comments, you can inflate your prediction success rate by predicting things that are 100% to happen. There are plenty of 99.9% bets on Polymarket with degens betting on some 0.01% lottery event trying to strike a jackpot against the odds, and those will inflate the perceived accuracy.
2. All you're really doing is paying insiders to leak information a few hours ahead of time. Insofar as Polymarket is unusually accurate on things that aren't ~100% to happen, it's likely because in the 12-hour-window that post measures is when all of the insiders place their last-minute bets telling you what will happen. This is extremely bad for society. It's wealth redistribution from stupid people to unethical people[1], and it could completely compromise national security when eg. an insider tells you 12 hours ahead of time that the US is about to launch an invasion of Venezuela. There is no societal benefit to this.
[1] Even if you have no sympathy for idiots who bet their life savings on markets without having insider information, gambling addiction has extremely detrimental effects on society and directly results in increased crime rates, divorce rates, etc. as people lose all of their money and do bad things in desperation, so it is a problem that becomes everyone else's problem.
1. That is not how prediction market calibration plots work! Calibration is measured across the range of markets with different forecasted odds.
https://calibration.city/introduction
https://manifold.markets/calibration
2. That is just obviously not all these markets are doing. They're aligning incentives and aggregating information in the same way other markets do.