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Prediction market vs sportsbook: what's the difference?
A sportsbook sets its own price for every ticket and builds its margin into the line. In a prediction market, trading sets the price. Each share pays $1.00 if its outcome happens, so the price is the market's chance of that outcome. GADUIN charges no trading fee.
At a glance
| Question | Sportsbook | Prediction market (GADUIN) |
|---|---|---|
| Who is on the other side | The bookmaker, at a line it sets | GADUIN fills every trade from a fixed pricing formula |
| Who sets the price | The bookmaker | Trading |
| What you receive | Your ticket amount times the sportsbook line, if your pick comes in | $1.00 per share on the outcome that happens |
| How it settles | The bookmaker's own rules against the official result | Terms fixed at open, applied to the official record |
| What it costs | A margin built into the line | No trading or settlement fee on GADUIN |
| Exiting early | Only if the bookmaker offers a cash-out price | No early exit on GADUIN: shares are held until settlement |
| What you can trade | Sporting events | Flights, trains, voyages, airports and shipping chokepoints |
1. Who is on the other side?
At a sportsbook, the bookmaker itself takes the other side of every ticket, at a price it chose. In a prediction market, the price comes from trading. On GADUIN, every trade is filled from a fixed pricing formula, and after a market opens only trades move the price.
2. Who sets the price, and how to convert it
A sportsbook quotes decimal or fractional lines. A prediction market quotes cents. To convert, divide: decimal line = 1 ÷ price, so 50¢ is a line of 2.00 and 25¢ is 4.00. A sportsbook's lines across all outcomes add up to more than 100%, and the excess is its margin. A prediction market's prices add up to about 100%.
| Prediction-market price | Implied chance | Decimal line | Fractional line |
|---|---|---|---|
| 10¢ | 10% | 10.00 | 9/1 |
| 20¢ | 20% | 5.00 | 4/1 |
| 25¢ | 25% | 4.00 | 3/1 |
| 40¢ | 40% | 2.50 | 3/2 |
| 50¢ | 50% | 2.00 | 1/1 |
| 60¢ | 60% | 1.66 | 2/3 |
| 75¢ | 75% | 1.33 | 1/3 |
| 80¢ | 80% | 1.25 | 1/4 |
| 90¢ | 90% | 1.11 | 1/9 |
3. What can you trade?
A sportsbook lists sporting events. A prediction market can list any question with a checkable answer. GADUIN lists transport only: whether a flight lands on time, whether a train runs late, whether a voyage makes port, how many aircraft land at an airport in a day and how many ships pass a chokepoint in a week.
4. How does it settle?
A sportsbook settles tickets under its own rules against the official result of the event. A prediction market publishes each market's terms before the first trade. On GADUIN those terms (the exact service, the reference time and the delay threshold) are fixed at open and applied to the official operational record: each share of the outcome that happens pays $1.00, and the rest pay $0. See how settlement works.
5. Fees vs built-in margin
A sportsbook rarely charges a visible fee. Its margin is built into the line. Prediction markets usually show their costs, and many publish a per-trade fee formula. GADUIN charges no trading fee and no settlement fee. You pay the market price and nothing else.
6. Can you exit early?
A sportsbook may offer a cash-out at a price it sets. Some prediction markets let you sell shares while trading is open. GADUIN doesn't. You can only buy, and shares are held until the market settles, so only put in money you can spare.
Regulation depends on the operator and the country
A sportsbook is usually licensed by a national or state gaming authority. Some prediction markets operate as regulated derivatives exchanges, for example under the CFTC in the United States. GADUIN is operated by Gaduin Inc., incorporated in Panama. It is not registered with, or licensed by, any securities or derivatives regulator, and it is not available to US persons or to residents of restricted jurisdictions. Check your local laws before trading.
Trading is risky. A position can settle at $0, so the full amount you put in is at risk.
Sportsbook questions
- Is a prediction market the same as a sportsbook?
- No. A sportsbook sets its own line and takes the other side of your ticket. A prediction market prices each outcome from trading, and every share pays $1.00 on the outcome that happens. How each is treated in law depends on the operator and the country.
- How do I convert a sportsbook line into a prediction-market price?
- Divide 1 by the decimal sportsbook line. A line of 2.50 is a price of 40¢, and a line of 1.25 is 80¢. A prediction market's payout multiplier is the same number: 1 ÷ price.
- Can I trade sport on GADUIN?
- No. GADUIN lists transport markets only: flights, trains, voyages, airport arrivals and weekly traffic through shipping chokepoints.
See a live price
Every GADUIN market shows its price as a chance and what a share pays out. Pick a flight that's about to board.
Keep learning
Start with the basics: What a prediction market is and how it works
Related guides
- How GADUIN compares with Polymarket and Kalshi
- How prices move: the LMSR pricing formula explained
- Prediction market payout calculator