Estimated outcome probability. A likely winner can still be overpriced.
← Decision briefsTennis · Oct 16, 4:15 AM PDT YOUR RESEARCH TASK FORECASTIga Swiatek RELIABILITY4/4 model reports MARKET VALUENot established Current TORK80.3% Simple average80.3% Calibrated average83.1% Kalshi80.0% Inspect the methods and progress →
Iga Swiatek vs Ann Li
80.3%Iga Swiatek
LOCKED Oct 16, 3:35 AM PDT4/4 independent models select Iga Swiatek; all four oriented probabilities average 80.25%.
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A documented difference, its timing, and limits.
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23 reported evidence limits. Agreement alone does not establish accuracy.
A probability difference alone does not account for forecast error, fees, spread, or available liquidity.
Why the models lean this way
These are reasons recorded by the models. They are not independently verified facts or measured causes of a probability change.
- Gemini: Swiatek's higher ranking (9 vs 31)
- Grok: Swiatek rank 9 with 3999 points vs Li rank 31 with 1648 points
- Claude: Ranking gap: Swiatek No. 9 (3,999 pts) vs Li No. 31 (1,648 pts)
- GPT: Current rank favors Iga Swiatek: 9 vs 31.
Read all four model reports
Gemini · Iga Swiatek · 82.0%
Iga Swiatek holds a significant advantage in both ranking and season performance. She is ranked No. 9 with 3999 points and a 39-15 record (72.2% win rate), while Ann Li is ranked No. 31 with 1648 points and a 25-24 record (51.0% win rate). The substantial gap in ranking points and win percentage makes Swiatek the clear favorite, though the lack of surface-specific form and head-to-head data limits absolute certainty.
google/gemini-3.1-pro-preview · Oct 15, 5:02 PM PDTGrok · Iga Swiatek · 80.0%
Iga Swiatek holds a substantially superior ranking (9 vs 31) and season record (39-15 vs 25-24) with one title compared to zero. These supplied facts indicate a clear edge for Swiatek. Surface form, injuries, head-to-head, travel, and market odds are unavailable as they are not supplied in the evidence package.
xai/grok-4.3 · Oct 15, 5:01 PM PDTClaude · Iga Swiatek · 81.0%
Swiatek is ranked 9 with 3,999 points versus Li's rank 31 and 1,648 points, a gap of roughly 22 ranking places and more than double the points. Season win rates reinforce the edge: Swiatek 39-15 (.722) with one title, Li 25-24 (.510) with none. Ranking-gap and win-rate baselines of this size on hard courts typically imply roughly a 78-84% win probability for the higher-ranked player in a WTA quarterfinal. Surface-specific form, injury status, head-to-head history, travel/scheduling load, and market odds are not supplied in the evidence package, so this estimate rests solely on current ranking and aggregate season record; I have shaded slightly below the extreme to reflect that missing context and the single-match variance inherent in best-of-three tennis.
anthropic/claude-opus-5 · Oct 15, 5:01 PM PDTGPT · Iga Swiatek · 78.0%
Using only the supplied immutable evidence, Iga Swiatek should be favored. She has the clearly superior current rank (No. 9 vs No. 31), substantially more ranking points (3999 vs 1648), and the stronger 2026 singles record (39-15 vs 25-24). That combination indicates a meaningfully higher baseline level and better season-long performance. This is a quarterfinal between two players who have both advanced deep into the event, so upset risk is still material, but on the limited evidence provided Swiatek is the stronger side by a clear margin. Surface form, injuries, head-to-head, travel, and market odds are unavailable in the evidence package and therefore cannot be used.
openai/gpt-5.4 · Oct 15, 5:01 PM PDTWhat remains uncertain
- Surface form is unavailable
- Injuries are unavailable
- Head-to-head records are unavailable
- Travel schedules are unavailable
- Market odds are unavailable
- Surface form unavailable
- Injuries unavailable
- Head-to-head unavailable
What to watch next
Official result recorded. Review the original forecast and sources below.
Open the event and source context →What changed before the lock
- 0.8 percentage points higher for Iga Swiatek
The pre-event probability state was locked atomically and is immutable.
Record hash
e3a2754cc70f1f79b0a9ca11c3a0000ab1443ccc6e77d355c9e82097e4b1ae10 - First recorded forecast
First prospective probability state captured for this source and competition.
Record hash
6336789211c7a8282665c30dc826c4f5724e87cd0231dbe950a1e48a478cf63a
Reasons are shown as they were recorded. The ledger does not establish that a specific fact caused a probability change.
The saved method comparison
All probabilities below refer to Iga Swiatek. Model inputs were fixed at Oct 16, 3:35 AM PDT. The market was observed at Oct 16, 3:30 AM PDT.
Comparison record
Saved Oct 16, 3:35 AM PDT. This is a research comparison; no method has been promoted.
45643740a2e1ff03e23243e2039447d06330972953ffb0317468ea60f2bd7a92Available source context
site.api.espn.com ↗sports.core.api.espn.com ↗sports.core.api.espn.com ↗sports.core.api.espn.com ↗sports.core.api.espn.com ↗sports.core.api.espn.com ↗site.api.espn.com ↗
These links provide event context. They do not verify every claim in a model report.
Recorded outcome: (7) Iga Swiatek (POL) bt Ann Li (USA) 6-4 6-1
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