What is implied probability in a prediction market?

Implied probability is the chance of an event happening, as estimated by the market price. On a binary contract that pays $1, the price in dollars is directly the implied probability. A YES contract at $0.42 implies a 42% chance. Comparing your own estimate to the implied probability is how traders find edge.

The prediction markets course — learn by doing

Polynate is the interactive prediction markets course built for beginners. It teaches you how prediction markets work, how venues like Polymarket and Kalshi actually price events, how to read a market price as a probability, and how to trade with discipline instead of guesswork. Short, hands-on lessons. Real market questions. Calibration tracking. No "lock of the day," no signals — just the math that separates traders who survive from traders who don't.

Start the prediction markets course for free — your first lesson takes about three minutes.

What are prediction markets?

A prediction market is an exchange where people trade contracts that pay out based on the outcome of a future event. Markets exist for elections, economic data releases, sports outcomes, geopolitical events, scientific milestones, policy decisions, entertainment, and almost anything verifiable. The price of a YES contract is the market's collective estimate of the probability that the event will happen. If a YES contract is trading at 63 cents, the market is implying a 63% chance of YES.

Prediction markets aggregate the views, information, and incentives of thousands of independent traders into a single number: the price. Decades of research — from the Iowa Electronic Markets in the 1980s to modern platforms like Polymarket, Kalshi, and Manifold — shows that well-designed prediction markets routinely outperform polls, pundits, and expert panels at forecasting real events.

How prediction markets work

Every prediction market has three components: a question, a resolution rule, and contracts. The question describes the event ("Will the Federal Reserve cut rates at the September 2026 meeting?"). The resolution rule defines exactly what counts as YES, what counts as NO, what counts as ambiguous, and what source of truth the market will use to decide. Contracts are the tradable instruments — typically a binary YES/NO pair that pays $1 to the winning side and $0 to the other when the market resolves.

Traders buy and sell YES and NO contracts before resolution. As new information arrives — a poll, a press release, a satellite image, a court ruling — prices move toward the new collective estimate. By the time the market resolves, the price usually converges to 0 or 100, depending on the outcome. Anyone holding the winning side gets paid $1 per contract; anyone holding the losing side gets nothing.

Polymarket, Kalshi, and the major venues

Polymarket is a crypto-native prediction market built on Polygon, where contracts settle in USDC. It is the highest-volume venue for political, sports, and crypto-related markets and has become the de facto place to read the global crowd's probability on breaking news.

Kalshi is a CFTC-regulated event futures exchange in the United States. It runs fully compliant US-dollar markets on economics, weather, elections, and entertainment, and is accessible to US residents through a regulated brokerage interface.

Manifold Markets uses play-money to run thousands of niche markets and is a great sandbox for learning. Metaculus is not a market in the strict sense but is the leading platform for tracking long-form expert forecasts. Polynate teaches the underlying skill that works across all of them.

Implied probability: the most important concept

The single most important skill in prediction markets is reading the price as a probability. On a standard binary contract that pays $1 at resolution, the price in dollars is the implied probability. A YES contract at $0.42 implies a 42% chance of YES. A YES contract at $0.85 implies an 85% chance. There is no other math — the price is the probability.

Trading edge comes from forming your own probability estimate before looking at the price, then comparing. If you believe the true probability is 55% and the market is priced at 42%, you have edge buying YES. If you think it's 30% and the market is at 42%, you have edge selling YES or buying NO. If your number is within a few percentage points of the market, you almost certainly do not have edge and the right trade is no trade.

Expected value, sizing, and resolution risk

Edge alone is not profit. Real prediction market trading requires three more skills that Polynate teaches in depth.

Expected value (EV) tells you how much a trade is worth in dollar terms. A YES contract bought at $0.42 with a true probability of 55% has an expected value of $0.55, for an expected profit of $0.13 per contract. Markets are won by repeatedly taking positive-EV trades.

Position sizing protects you from the inevitable variance. The Kelly criterion gives a mathematically optimal stake size, but most traders should use fractional Kelly or a fixed-fraction rule to survive bad streaks and stay in the game.

Resolution risk is the silent killer. A "clear" market often has ambiguous edge cases — what if the event is delayed, what if the official source changes its mind, what if the wording is interpreted differently by the resolver? Polynate trains you to read resolution rules like a contract lawyer before you put money on a question.

The Polynate curriculum

Polynate is structured as short, gated lessons that build mastery one concept at a time. The full curriculum covers: probability foundations, reading YES/NO contracts, implied probability, understanding resolution rules and ambiguity, market microstructure (order books, liquidity, spreads), expected value and Kelly sizing, post-trade review and calibration tracking, common beginner mistakes, and the differences between Polymarket, Kalshi, Manifold, and Metaculus.

Each module ends with a real market question. You make a prediction, the lesson reveals the actual market price and resolution, and you build calibrated intuition trade by trade.

Prediction markets guides

In-depth, free guides on the core concepts every prediction market trader needs. Each guide complements the full Prediction Markets Course.

Polynate by audience

Who Polynate is for

Polynate is built for beginners. If you've never traded a prediction market, you'll start at the beginning and never feel lost. It's also useful for experienced forecasters who want to formalize their process, sports traders transitioning to event markets, finance professionals exploring a new asset class, journalists and researchers who want to read market prices accurately, and anyone who wants to think more clearly about probability and uncertainty.

Prediction markets — frequently asked questions

What is a prediction market?

An exchange where you trade YES/NO contracts on future events. The price of a contract is the market's estimated probability of that event happening.

How do prediction markets work?

Each market has a clearly defined resolution rule. YES and NO contracts trade between participants. At resolution, the winning side pays $1 per contract and the losing side pays $0.

What is implied probability?

The market price in dollars equals the market's estimated chance of YES. A $0.42 YES contract implies a 42% probability. A $0.85 contract implies 85%.

Is Polymarket legal in the US?

Polymarket is not currently available to US residents. Kalshi is the leading CFTC-regulated alternative for US users. Polynate teaches the underlying skill, which transfers across venues.

How is Polynate different from just trading on Polymarket or Kalshi?

Polymarket and Kalshi are venues — they let you place trades. Polynate is a course that teaches you how to trade. Most beginners lose money because they misread resolution rules, anchor on intuition, or size positions emotionally. Polynate fixes that before you risk capital.

Is Polynate for beginners?

Yes. Lessons assume zero prior experience and build from the basics through advanced topics like Kelly sizing and calibration tracking.

How long is the prediction markets course?

The full prediction markets course is about five hours of total content, broken into short interactive lessons of roughly ten minutes each. Most learners take it over two to four weeks at a pace of one lesson per day.

Is the prediction markets course free?

The first lesson is free with no signup required. Full access to the prediction markets course is a one-time $19 unlock — no subscription, no recurring fees.

Who is the prediction markets course for?

The prediction markets course is built for beginners. It assumes zero prior experience with prediction markets, sports trading, or finance. It is also useful for experienced forecasters who want to formalize their process, sports traders moving to event markets, and analysts who want to read market prices accurately.

Does the prediction markets course cover Polymarket and Kalshi?

Yes. The course teaches the underlying skill that works across every major prediction market venue, including Polymarket, Kalshi, Manifold Markets, and Metaculus, with specific lessons on the differences between each.

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