Who Wins in Prediction Markets? Analyzing Polymarket Data
Prediction markets have long been touted as the 'oracle' of truth, often outperforming traditional polling in forecasting outcomes. However, the internal dynamics of these markets—specifically who actually makes money—remain largely opaque. A recent study analyzing 588 million trades ($67 billion in volume) on Polymarket, the largest prediction market, provides a window into the professionalization of these platforms.
The Pareto Distribution of Profit
One of the most striking findings of the study is the extreme concentration of wealth. The researchers found that the top 1% of users capture 76.5% of all profits. This distribution suggests that prediction markets are not merely casual gambling hubs, but environments where a small group of sophisticated actors dominate the financial outcomes.
This concentration is driven by a fundamental difference in trading behavior: the distinction between liquidity providers (makers) and liquidity takers (takers).
Makers vs. Takers
Successful traders on Polymarket typically act as liquidity providers. They use limit orders, which allow them to specify the price at which they are willing to buy or buy into a position. By providing liquidity to the market, they essentially act as market makers, capturing the spread and managing risk across various outcomes.
In contrast, unsuccessful traders typically use market orders, which are the primary tool of the 'takers.' These traders often act on directional bets—betting on a specific outcome they believe will happen—and often do so with less discipline, effectively paying a premium to the professional liquidity providers.
Debunking the 'Insider' Myth
A common assumption is that the most successful traders in prediction markets are those with 'inside information'—people who know the outcome of an event before the rest of the market does. However, the data suggests otherwise. The study concludes that "insider" trading is unlikely to explain the performance of the largest winners.
Instead, the performance of the top 1% is attributed to disciplined liquidity provision and technical edge. This finding is supported by the comments from the industry, noting that the most successful accounts often employ strategies that are more durable than simple event-specific alpha.
The Role of Sports Betting and Arbitrage
Beyond the general mechanics of trading, the specific markets where these gains are realized provide further insight into the sports-centric nature of these profits.
- Sports Markets: The study found that 81% of the gains were realized in sports markets, often involving bets on different teams. This suggests that professional sports bettors—who are often banned from traditional sportsbooks—may be migrating to Polymarket because it is permissionless and does not limit winning users.
- Cross-Venue Arbitrage: Some community members pointed out that what looks like "skill" on a single platform may actually be be cross-venue arbitrage. Traders using high-speed infrastructure to monitor prices across Polymarket, Kalshi, and Smarkets may be capturing gaps of 3-8% between venues. In this case, the "skill" is not necessarily about predicting the future, but about having superior technical infrastructure to execute trades faster than the lagging book.
Critical Perspectives and Societal Impact
While the technical analysis of the data is the study's primary focus, the discussion around these markets raises broader questions about the societal impact of prediction markets.
"In terms of damage to society it's irrelevant who the winners are within the Polymarket system, it matters how much the insiders playing on Polymarket have an effect to the outside world of politics and economics."
This perspective highlights the tension between prediction markets as tools for information aggregation and prediction markets as vehicles for corruption or incentive structures that reward the opposite of public interest.
Conclusion
The Polymarket data reveals a prediction market that is maturing into a professionalized financial ecosystem. The gap between the top 1% and the rest of the rest is not based on secret knowledge, but on the technical ability to provide liquidity and the a disciplined approach to risk management. For the rest of the users, the majority of the most likely outcomes are effectively subsidized by the 'daredevils' and 'amateurs' who use market orders to execute directional bets.