What will the average number of measles cases be during Trump's term?
Based on CDC annual totals for 2017–2020, the arithmetic average is exactly 447 cases/year; I assess ~99% probability that the market should resolve to that value under the stated interpretation.
Analysis
**Stage 1 — Blind analysis (ignore market prices):**
- The question as written in the recent context is explicit: the Trump Administration is defined as January 20, 2017–January 20, 2021 and the recent news provides CDC-confirmed calendar-year counts for 2017–2020: 121, 372, 1,282 and 13 respectively. Summing those gives 1,788 total cases across the four calendar years and dividing by 4 yields an average of **447 cases per year**.
- If the contract’s intended measure is the simple arithmetic mean of annual confirmed U.S. measles cases for the four calendar years overlapping the administration (2017, 2018, 2019, 2020), that calculation is deterministic and supported by primary-source CDC surveillance numbers. The only realistic sources of error are (a) any deliberate alternate interpretation of the date range (e.g., counting partial years differently), or (b) retrospective revisions to surveillance totals by the CDC.
- Historical practice: many retrospective event-statistics questions use calendar-year aggregates when asking for per-year averages for a presidential term. Under that conventional interpretation, the figure 447 is not an estimate but a computed fact from published surveillance data.
- Likelihood of substantive CDC revision that would shift the average materially is very low. Measles case counts are confirmed case surveillance that can be adjusted slightly on rare occasions, but changes large enough to move a 447 average materially (e.g., tens or hundreds of cases) are improbable.
- Given these points, my independent (blind) probability that the correct resolved average—under the conventional calendar-year interpretation—is essentially certain. I assign **~99%** to the 'Yes' outcome if 'Yes' means that the average equals the computed 447 (or that the canonical calculation using those four years yields 447). I avoid stating absolute 100% only to allow for the tiny chance of classification/revision/resolution-operator interpretation edge cases.
**Stage 2 — Market calibration (now consider market prices):**
- Current market pricing is: Yes 0.3 / No 0.7. That implies market participants assign only a 30% chance that the event will resolve to 'Yes'. This is a large divergence from the near-certain arithmetic result.
- Potential explanations for the market discount (why price is low): - *Ambiguity in the contract wording or resolution criteria.* If the contract actually uses a different numerator/denominator (for example, counts during Jan 20, 2017–Jan 20, 2021 daily totals rather than calendar-year totals), traders may believe the canonical 4-calendar-year method is not the one that will be used to resolve the market. The event title mentioning 2025–2028 (contradiction in the metadata) could be sowing confusion. - *Participants may suspect a nonstandard rounding or threshold.* If the binary contract tests a comparison (e.g., “Is average > X?”) rather than equality to 447, traders may be pricing that alternate predicate rather than the explicit average calculation shown in the news context. - *Illiquid or misinformed trading.* Despite sizable volume, a subset of traders might be betting on phrasing ambiguity or on the improbable chance of data revision. Some traders may not have inspected CDC totals and are relying on gut instincts about measles trends. - *Possible disagreement about whether the administration period includes a partial 2017 and partial 2021 and should use those partial-year counts instead of full calendar years.* If the contract were interpreted by the resolution source to compute the average using cases that fell strictly inside Jan 20, 2017–Jan 20, 2021 (i.e., excluding 2017 calendar days before Jan 20 and including 20 days of 2021), the total could differ slightly from the 1,788 figure used above.
- Calibration conclusion: the market likely reflects confusion or ambiguity rather than new evidence that the arithmetic is wrong. If the contract actually resolves using the calendar-year totals explicitly named in the provided context, the market is mispriced and 'Yes' is dramatically underpriced. If, however, the contract uses a nonstandard resolution methodology (partial-year counts, alternative denominator, or a comparative threshold), then the market price may reflect that interpretation and my high-confidence assessment would not apply.
- Practical implication for traders: If you can verify the contract’s precise resolution language (what exact counts/dates and rounding rules the oracle will use), there is likely an actionable edge: if the resolution uses calendar-year totals 2017–2020 as stated, buying Yes is a high-probability arbitrage play; if the resolution uses a different definition, evaluate that definition against CDC datasets before trading.
Arguments
For
- Authoritative source: CDC surveillance totals for 2017–2020 are published and sum to 1,788, producing an arithmetic average of 447—this is a straightforward, reproducible calculation.
- Conventional handling: many retrospective averages for presidencies are computed using calendar-year totals; the recent news uses that method explicitly.
- Low likelihood of large-data revision: confirmed case totals are seldom revised by large amounts after publication, making the computed average highly stable.
- Deterministic arithmetic: absent ambiguity about the denominator or date-bounds, the answer is a calculation, not an uncertain forecast.
Against
- Contract wording ambiguity (calendar-year versus exact-term-day counting) could change the resolved number and appears to be a real source of market confusion.
- Metadata inconsistency (event title listing 2025–2028) may have led traders to disregard or misread the provided CDC-year calculation.
- Small chance of surveillance reclassification or late-added cases that could alter totals modestly and thus change the mean by a nonzero amount.
- If the market's 'Yes' predicate is actually a threshold/comparison or a different numeric target (not equality with 447), then the 30% price may reflect a different question entirely.
Key drivers
- CDC-confirmed annual measles case totals for 2017–2020 (121, 372, 1,282, 13)
- Contract's precise resolution language (calendar-year vs. strict Jan20–Jan20 counting)
- Likelihood of retrospective CDC data revision or reclassification
- Market participant interpretation/attention to the event metadata (title mismatch 2025–2028)
Risk factors
- Resolution ambiguity: if the oracle uses partial-term daily counts rather than calendar-year totals, the computed average could differ.
- Post-publication CDC revisions to surveillance totals (low probability but nonzero).
- Market misinterpretation or manipulation causing price divergence from the true arithmetic fact.
- Possible discrepancy between the event description provided to traders and the actual resolution rules used by the platform.
Scenarios
Best case
Resolution uses calendar-year CDC totals for 2017–2020 exactly as presented. The arithmetic average is 447 and the contract resolves to 'Yes' with near certainty; arbitrage opportunity exists if the market remains at Yes=0.3.
Most likely
The resolution will follow published CDC calendar-year totals or equivalent methodology; therefore the correct answer is the computed 447 average and 'Yes' should be considered nearly certain—market pricing appears to reflect confusion rather than substantive uncertainty.
Worst case
The platform resolves using a different definition (e.g., counts strictly within Jan 20, 2017–Jan 20, 2021, or a different rounding/threshold), or the CDC materially revises counts during adjudication; as a result the 'No' side prevails and the market price reflects that uncertainty.
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