Polymarket vs Polls: Why Markets Beat Experts

By mid-October 2024, Polymarket had Trump at 60%+ and rising. Virtually every major poll had the race within margin of error, with most showing Harris with a slight edge. The polling consensus was a coin flip. The market consensus was a clear Trump lead.

Election night: Trump won with more electoral votes than most polls predicted. Polymarket was closer to right. This wasn't a fluke — it was the fourth consecutive major election cycle where prediction markets outperformed the polling average.

Markets aggregate private information. Every trader who buys Trump at 60% is revealing that they believe the true probability is above 60%. Maybe they've seen internal polling. Maybe they're modeling early vote patterns. Maybe they have ground truth from canvassing. The price reflects all of that.

Polls can't aggregate private information. They ask a representative sample what they plan to do. That sample may not accurately reflect the actual electorate, may not tell the truth, and the pollster's methodology choices can compound these errors.

Polling firms herd. They look at other polls and adjust their methodology to avoid being the obvious outlier. This creates systematic bias — when the true result is far from consensus, every pollster misses in the same direction.

Market participants are rewarded for being right, not for being in consensus. A trader who correctly disagrees with the market consensus profits. There's no equivalent incentive in polling — being the one outlier poll that turned out to be right doesn't pay off for the pollster.

Markets aren't perfect. They can be manipulated with large positions. They can anchor on media narratives if enough retail traders are following news rather than trading on information. Illiquid markets are especially vulnerable to noise.

The 2024 election market was extremely liquid and hard to manipulate. Smaller markets — state-level results, specific congressional races — were thinner and showed more noise. The quality of market signals scales with liquidity.

The prediction market track record should be the death knell for 'polling averages' as a news product. They're worse information than the freely available market prices. Every time a major outlet reports polling numbers without mentioning prediction market odds, they're making a choice to give their audience worse information.

This will change. Slowly, because institutions change slowly. But the next generation of political journalists will report prediction market prices the way financial journalists report stock prices. The information is just too good to ignore.