Event market arbitrage analysis needs a complete description of what the account receives in each relevant outcome. A sum of prices is meaningful only after that description exists. Buying several cheap-looking outcomes does not establish a fixed combined payout, and buying different quantities of an otherwise complete set changes the result. A plain-language payoff matrix can expose these issues before any order is considered.
The method is simple: name a possible state, identify the positions that pay in that state, add their payouts and subtract the full acquisition cost. Repeat for every ordinary outcome and every contractual exception that matters. Then consider whether the quantities can actually be acquired and how long the funds remain committed. The examples below are fictional and assume stated one-dollar or zero payouts where specified; they do not claim that any live venue offers the illustrated relationship.
An Event Market Arbitrage Payoff Matrix Can Be Written in Prose
Start with a fictional event that has exactly three mutually exclusive and exhaustive ordinary outcomes: A, B and C. Each outcome contract's Yes position pays one dollar if that outcome occurs and zero otherwise. Assume the same source, deadline and outcome definitions apply to all three. The rules for exceptional states will be considered separately rather than silently excluded.
If the account owns 100 Yes units in each outcome, the A scenario pays $100 from A and zero from B and C. The B scenario pays $100 from B and zero from A and C. The C scenario pays $100 from C and zero from A and B. The combined ordinary payout is $100 in all three cases. This statement is the payoff matrix, expressed in sentences rather than a grid.
Now write the assumptions that make it valid. Exactly one ordinary outcome must occur. Every held unit must have the stated payout. The contract definitions must refer to the same event and observation convention. If two outcomes can both qualify, or if an unlisted outcome can occur, the constant-payout conclusion does not follow. The proof belongs to the rules, not to the fact that the contracts appear beside one another on a screen.
The older guide on how to arbitrage Polymarket provides context for examining outcome relationships. The general analytical habit is to describe the payout without using price as evidence of meaning. Only after the structure is clear should the trader ask whether the cost of obtaining it is favorable.
Separate Exclusivity From Exhaustiveness
Mutual exclusivity means that no allowed ordinary state makes two members win together. Exhaustiveness means that every allowed ordinary state makes at least one member win. These properties solve different problems. A list of named candidates for one position can be exclusive while omitting a possible replacement candidate. A list of overlapping numerical ranges can cover all values while allowing more than one winning contract at a boundary.
For a fictional committee appointment, contracts on three named people are not exhaustive if the rules permit someone else to be appointed. Buying all three Yes positions can then produce zero if an unlisted person is selected. An Other contract might complete the set, but only if its definition covers the remaining states in a compatible way. The label alone is insufficient; read what it includes and excludes.
Likewise, ranges described as below 10, from 10 through 20 and above 20 can form a complete partition of valid numbers if the boundaries are defined consistently. If another contract instead uses at least 20, the value 20 may belong to two outcomes. A small wording difference can change the maximum payout and the relationship among prices. Include exact boundary observations in the walkthrough.
Polymarket's markets and events documentation distinguishes event grouping from individual market structure. An analyst should verify the actual relationship among the selected contracts. Organizational proximity is useful for discovery, but it is not a substitute for proving that the proposed holdings cover the intended states in the intended proportions.
Compare the Cost With the Correct Payout
Suppose the fictional A, B and C asks are $0.25, $0.30 and $0.41, with enough available quantity to acquire 100 units of each at those prices. Purchase costs are $25, $30 and $41, totaling $96. Assume the actual combined acquisition charges for this teaching example are $2. Total cost is $98 against the $100 ordinary payout established by the equal-quantity matrix.
The modeled difference is $2. Dividing by the $98 committed gives approximately 2.04% for this one completed structure, under all the stated assumptions. That percentage is not an annualized result and is not a prediction that the trade can be repeated. It also does not incorporate any unmodeled funding, transfer or exceptional-settlement cost. The purpose of the example is to identify exactly what the arithmetic assumes.
Use executable asks for purchases, including the full depth required by the intended size. If one outcome has only 20 units available at the best ask, the other 80 need their own prices. A displayed reference value or recent trade does not establish that quantity. Each additional price level changes the acquisition total, and the most expensive required leg can eliminate a small difference between cost and payout.
The fee assumption must also match the actual action. Use current market-specific terms and reconcile reported charges after execution. Polymarket's fee documentation identifies differing market fee parameters. The $2 used here is an invented total for the example, not an estimate of what any named platform would charge for the three hypothetical contracts.
Event Market Arbitrage Unequal Quantities Change the Matrix
Suppose the intended 100-unit positions do not all fill. The account acquires 100 A units, 80 B units and 100 C units at the same example prices. Purchase cost is now $25 plus $24 plus $41, or $90. Assume total actual charges for this separate example are $2, making the acquisition cost $92. The lower cost does not mean the structure became more attractive, because its payout changed as well.
If A occurs, the account receives $100 and has an $8 result after the stated acquisition cost. If B occurs, it receives only $80 and loses $12. If C occurs, it receives $100 and gains $8. The minimum ordinary payout is $80, not $100. A report that compares the $92 cost with a presumed $100 payout in every outcome would conceal the missing 20 B units.
The account contains 80 complete sets plus 20 extra A units and 20 extra C units. At the example purchase prices, the 80 complete sets cost $76.80 before charges. The extra units cost $5 for A and $8.20 for C, totaling $13.20. Together these amounts reproduce the $90 purchase total. This decomposition helps identify which part has the constant ordinary payout and which part retains outcome exposure.
The related event market arbitrage bot article examines recovery when the intended structure is incomplete. The matrix should be recalculated from confirmed fills as they arrive. A pending order for the missing B units represents possible future completion; it does not belong in the current payout column until it actually fills.
Exceptional States Need Their Own Branch
A mathematical partition of ordinary outcomes can still omit a contractual exception. The underlying event might be cancelled, a required source might not publish or a resolution process might apply a special treatment. Read the terms for every leg and describe the payout in that state. If the contracts use different exceptional rules, their ordinary compatibility may not extend to the exception.
For example, suppose two fictional contracts return their acquisition amounts in a cancellation while a third follows a different fixed payout rule. The combined cancellation result depends on those provisions and the prices actually paid. It cannot be inferred from the one-dollar ordinary payout model. The analyst must calculate the state separately or mark the candidate unresolved until the terms are understood.
A delayed resolution is different from a reduced payout. It may preserve the ultimate amount while changing the time at which the account can use it. A disputed interpretation can affect both amount and timing. The scenario record should distinguish these effects so that a capital plan does not confuse eventual economic value with currently available cash.
The narrower event contract arbitrage guide focuses on matching contract terms and funding the required legs. This matrix method complements that work by requiring a plain statement for every relevant branch. A candidate should not be described as producing a constant payout when its documentation contains an unexamined state capable of changing that payout.
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Event Market Arbitrage Capital Lockup Changes Practical Capacity
Capital lockup is the period during which funds committed to the structure cannot be used for another purpose under the actual account mechanics. Do not assume a complete set can be converted back into spendable funds before settlement unless the specific product supports a verified mechanism and the account can use it. The teaching example here assumes the positions are held until their final payout becomes available.
With a $1,000 budget, ten of the $98 structures would commit $980 and leave $20 uncommitted under the simplified assumptions. If the payout becomes available after two days, the budget is tied up for two days. If it takes twenty days, the same projected $20 total gain from the ten structures requires a much longer commitment. The nominal difference between cost and payout is unchanged, but the opportunity to use the capital elsewhere is different.
Do not turn the two-day example into a confident repeated annual return. It assumes neither a new opportunity every two days nor identical costs, depth and settlement behavior. A useful report states the actual acquisition amount, projected payout, elapsed time and unresolved cases. Those facts are more informative than an annualized figure built on a repetition assumption the evidence does not support.
A capital plan should include idle funds needed to support future legs or separate accounts. If the workflow keeps additional money ready on another service, that allocation is part of the resources required to operate the strategy. Measuring return only against the cheapest completed position can understate the capital base that makes the process feasible.
Track Where the Winning Cash Flow Will Arrive
A constant total payout does not imply a constant location for the proceeds. If different outcomes are held in different accounts, the winning cash flow may arrive in a different place depending on the event. The overall portfolio can receive the expected amount while one account remains underfunded for its next task. Funding capacity is local as well as aggregate.
In a fictional cross-account version, A is held in Account North, while B and C are held in Account South. If A wins, the ordinary payout arrives in North. If B or C wins, it arrives in South. The desk should not assume that a future opportunity requiring funds in the other account can be used immediately. Transfer availability, timing and applicable account rules need separate verification.
The older Polymarket and Kalshi dual-market bot article is useful context for coordinating separate account environments. The comparison must identify the actual permitted venue contexts, including the distinction between Polymarket International and Polymarket US where relevant. A shared brand or visible market does not establish shared balances, transferable permissions or equivalent contract terms.
Record expected and realized cash location in the settlement review. This helps explain why a theoretically neutral portfolio may still require operational reserves. It also prevents the strategy from treating an anticipated payout in one account as available funding for an order somewhere else. The payoff matrix describes the amount by state; the funding map describes where and when that amount can be used.
An Exit Before Resolution Uses a Different Matrix
The constant ordinary payout in the teaching example assumes the required positions remain held through resolution. Selling before then creates a new transaction whose proceeds depend on executable bids. A complete set can be worth one dollar at final payout under the rules while its immediate sale proceeds are lower after spreads and fees. The account should not assume that the final payout is available as an immediate exit price.
Suppose the 100-unit A, B and C positions can currently be sold at bids of $0.23, $0.28 and $0.39. Immediate sale proceeds would total $23 plus $28 plus $39, or $90 before exit charges. Compared with the example's $98 acquisition cost, that is an $8 loss before any exit charges. This does not contradict the modeled $100 final payout; it reflects a different action at different executable prices.
The exit decision should compare remaining expected obligations, current proceeds, time and account constraints. A participant who needs funds immediately may accept a loss to free capacity. Another may retain the structure if its terms remain valid and the capital commitment remains acceptable. The choice needs its own authorization rather than being implied by the original entry analysis.
The older Kalshi odds arbitrage bot discussion offers another setting where price relationships and executable exits must remain distinct. A report should clearly label whether a value represents final modeled payout, current liquidation proceeds or a forecast-based estimate. Those labels prevent a paper gain from being mistaken for money already available to the account.
Separate Logical Proof From Operational Evidence
The payoff matrix proves a relationship only within its assumptions. Operational records establish whether the account actually acquired and retained the required positions. Keep both types of evidence. The reviewed contract mapping should explain why the payouts combine as stated. Fill records should establish quantities and prices. Account reconciliation should establish the remaining positions and final proceeds.
An event contract bot needs explicit state handling to preserve that evidence. An unknown submission can leave an order live even if the local process did not receive confirmation. Repeating the request can overfill one outcome and change the matrix. A cancellation can also leave additional fills that must be incorporated before the case is considered complete.
For each case, compare intended quantities with actual quantities and explain every difference. If a deliberate residual position remains, assign it to a documented risk decision rather than leaving it hidden inside a completed-arbitrage label. A case can finish its execution workflow while still carrying risk, but the account record must make that remaining risk visible.
Review exceptions across cases. If the same contract family repeatedly produces rule ambiguity, if one leg repeatedly lacks depth or if settlement timing regularly exceeds the plan, the candidate-selection process may need revision. A logically attractive structure is not automatically an operationally useful one. The evidence should support both the payout claim and the practical process required to obtain it.
Use the Matrix to Define a Decision Boundary
Before entering, specify the minimum modeled payout, maximum total cost, supported exceptional states and permitted unfinished exposure. These conditions define when the candidate is acceptable. If actual quotes, fees or quantities move outside them, the system should decline or seek a new bounded decision. It should not preserve the original label while quietly changing the economics.
The three-outcome example makes this boundary concrete. Equal 100-unit holdings cost $98 under the assumptions and have a $100 ordinary payout. Unequal holdings of 100, 80 and 100 cost $92 but have a minimum ordinary payout of $80. The cheaper incomplete structure is not a better version of the same trade. It is a different distribution of results and must be judged as such.
After settlement, compare each realized cash flow with the scenario that occurred. Confirm the quantities, charges and account location, then record elapsed time. If the result differs from the matrix, investigate whether the cause was a rule misunderstanding, execution difference or accounting error. A small unexplained discrepancy can expose a repeatable process flaw even when the overall case happened to be profitable.
A prose payoff matrix is useful because it forces the proposed combination to make sense one outcome at a time. It connects contract meaning with quantities, cost and capital timing. That connection is the foundation of event-market arbitrage analysis; the price gap becomes informative only after the account's possible results are explicit.