How prices work as probabilities
In a prediction market, price and probability are the same number wearing two hats: 62¢ is both what a Yes share costs and the crowd’s 62% estimate that Yes happens. Master that equivalence and every market becomes readable.
In a market that pays $1 for a correct “yes,” the price and the probability are the same number So reading a market is just reading a percentage, and the money is made when that percentage is wrong.
Every skill in prediction markets sits on one translation: the price is the probability. It sounds like a slogan; it is actually a mechanism. Walk through why it must be true, and the rest of the craft, payouts, moves, mispricings, falls into place.
01Why the equivalence holds
A Yes share pays $1 if Yes happens, $0 if not. Suppose the true chance of Yes is 62%. Then a share is worth, on average, 62¢. That is just 62% of a dollar. If it traded at 50¢, buyers would pile in for the bargain and push it up; at 80¢, sellers would take the gift and push it down. Money hunting mistakes is what pins the price to the crowd’s best estimate of the chance.
02Reading any price at a glance
| Price | Crowd’s estimate | If you buy Yes and win | If you lose |
|---|---|---|---|
| 20¢ | ~20% chance | +80¢ per share | −20¢ |
| 50¢ | ~50% chance | +50¢ | −50¢ |
| 62¢ | ~62% chance | +38¢ | −62¢ |
| 90¢ | ~90% chance | +10¢ | −90¢ |
Notice the trade-off written into the table: likely outcomes pay little, longshots pay a lot, if they land. Neither end is “better.” What matters is whether the price is wrong, in either direction.
03Prices move because beliefs move
An injury report, a poll, a court date moved, each piece of news changes what the crowd believes, and the price follows within minutes. Watching a market drift from 55¢ to 70¢ is watching a probability update in public. The speed is a feature: it means today’s price already contains almost everything public. Almost.
04When the number is wrong
Crowds misread dull evidence, chase drama, and update late. When the price says 62% but the evidence supports 75%, the 13-point gap is edge And buying it is a positive-expected-value bet even though it loses a quarter of the time. That last clause is the whole discipline: probabilities pay off across many bets, never one at a time.
An 80¢ favorite still loses one time in five. Being right about the probability and losing the bet can happen on the same afternoon, size for it.
This is the lens your CEO applies to every market it opens: translate the price, form its own estimate, and act only on the gap. The one-paragraph version lives in the FAQ: how prices become probabilities.
How your CEO runs the numbers
A market reads 68¢ for “yes.” That is the crowd saying 68% No conversion needed. If your CEO’s research lands at 80%, it sees a 12-point gap and a reason to buy. If its own number is also about 68%, there’s no edge and it moves on. The price is the probability; the work is deciding when that probability is wrong.
Common misreads
- Reading the price as a target, not a probability. 70¢ doesn’t mean “headed to $1”. It means a 70% implied chance right now.
- Confusing a moving price with rising certainty. A price drifting up reflects shifting belief, not a guarantee the answer is yes.
- Assuming the crowd is always right. The price is the crowd’s estimate, and the whole point of your fund is the times it’s wrong.
What to remember
- Price and probability are the same number here, 71¢ is a 71% chance.
- You can read any market at a glance once you see it as a percentage.
- Prices move because beliefs move, not because supply runs out.
- Your fund acts only when it can argue the number is wrong, and by how much.