Binary vs Scalar Contracts
Definition
A binary event contract has two outcomes and pays a fixed amount, usually $1, if the event occurs and zero if it does not. A scalar contract pays an amount between zero and the maximum that depends on where a measured outcome falls within a stated range. Range or bracket markets split an outcome into several binary contracts, one per interval, so that exactly one should pay.
Why it matters
Payout shape decides how much a small error in a forecast costs. A binary contract concentrates risk at its threshold, so a value just on the wrong side loses everything. Investors should check the payout schedule, any fair-value or split settlement rules, and liquidity, which is often thinner in range and multi-leg products.
Common misconceptions
- •A range market of several binaries is not the same as one scalar contract; each leg has its own price and spread.
- •A combo is its own market; its payout multiplies the legs' settlement values.
- •Partial or fair-value settlement can occur even in contracts that look binary.
- •The label is only a starting point. Investor outcomes usually depend on the governing documents, cash-flow priority, valuation policy, disclosure quality, and manager discretion surrounding the term, not just the shorthand definition used in marketing materials.
Technical details
Worked example (illustrative)
Binary: 'Will the rate exceed 4.00%?' pays $1 if the published rate is 4.01% and $0 at 4.00%.
Scalar: pays linearly from $0 at 3.50% to $1 at 4.50%; at 4.00% it pays $0.50, at 4.20% it pays $0.70.
Range set: five brackets of 0.25 points each; exactly one bracket pays $1.
How investors apply the term
Investors usually apply this term by tying the definition back to the controlling documents and then asking which cash flows, rights, restrictions, or valuation assumptions it changes. A useful review looks at the term alongside fees, leverage, liquidity, reporting frequency, and manager discretion rather than treating it as a standalone concept.
The practical diligence test is simple: identify who benefits if the assumption is wrong, who has control when conditions change, and what evidence the investor receives after closing. Terms that cannot be reconciled to documents, cash movements, and monitoring data should be treated as marketing shorthand until proven otherwise.
Frequently asked questions
- What is the difference between binary and scalar prediction markets?
- A binary contract asks whether something happens and pays all or nothing. A scalar contract asks how much, and pays proportionally. The CFTC describes the traditional structure as 'all-or-nothing' and notes some frameworks 'include outcome ranges that offer partial payouts instead.'
- Can a binary contract pay something other than $1 or $0?
- Sometimes, under its rules. Kalshi says that in some cases 'a market can resolve to the last fair market price or a non-standard payout like 50-50.' In a combo, 'the payout is the product of all individual position values': if two legs resolve to $1.00 and one to $0.70, the combo pays $0.70 per contract.
- Which is riskier?
- They spread risk differently. A binary position near 50 cents can lose its whole cost on a small difference in the outcome. A scalar position loses gradually as the outcome moves away from the trader's view. The CFTC notes that more complex contracts 'may attract fewer participants, resulting in comparatively lower liquidity.'