Start with the price
Trading in prediction markets means comparing your estimate of an outcome's probability with the price of its contract. An outcome can be likely and still be overpriced. Professional forecasters look for gaps between market odds and their own assessments.
Spotting mispriced odds
Emotions and cognitive biases can push market prices away from what the data suggests. In political markets, for example, supporters may overpay for contracts on their preferred candidate. Professional traders compare prices with statistical models to look for a trading edge.
Several patterns can point to a pricing error:
- Recency bias can cause traders to overreact to the latest news.
- Favorite-longshot bias can leave likely outcomes underpriced and unlikely outcomes overpriced. It is not a reliable signal in every market.
- Low liquidity means a single large trade can temporarily move the price in a small market, creating an opportunity for smaller traders.
Trading on specialist knowledge
Information arbitrage means buying contracts before market prices fully reflect new information. Expertise in a regulatory framework or weather patterns, for example, may help you interpret news before other traders do.
Settlement time affects how long capital remains committed. Faster settlement can release funds sooner, but it does not guarantee higher returns. Fees, losses and the availability of another worthwhile trade still matter.
Managing risk
Even a confident forecast can be wrong. The Kelly criterion is a mathematical approach to position sizing that depends on estimated probabilities and payoffs. If those estimates are wrong, the calculated position can be too large; the formula does not remove the risk of losing money.
Habits for managing your exposure
- Never bet more than you can afford to lose.
- Spread your exposure across unrelated markets. Several contracts on the same election can still leave you dependent on one result.
- Keep a record of every trade and review your reasoning afterward. Note what held up and what you got wrong.
Hedging a business risk
Businesses can use prediction markets to offset the cost of a specific outcome. A company that relies on international trade might buy "Yes" contracts on a proposed tariff. If the tariff takes effect, the payout can help cover the company's higher costs.