Estimated outcome probability. A likely winner can still be overpriced.
← Decision briefsTennis · Oct 18, 9:00 PM PDT FORECASTPeyton Stearns RELIABILITY4/4 model reports MARKET VALUENot established
Peyton Stearns vs Katerina Siniakova
65.8%Peyton Stearns
NOT LOCKED4/4 independent models select Peyton Stearns; all four oriented probabilities average 65.75%.
20 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.
- Grok: Stearns current rank 37 beats Siniakova rank 87
- Claude: Ranking gap: Stearns No. 37 vs Siniakova No. 87 (1316 vs 855 points)
- Gemini: Stearns is ranked 50 places higher than Siniakova (37 vs. 87).
- GPT: Stearns holds the better current ranking: 37 vs 87.
Read all four model reports
Grok · Peyton Stearns · 67.0%
Stearns holds the superior current rank (37 vs 87), more ranking points (1316 vs 855), and a stronger season record (25-22 vs 18-18 with one title). These supplied facts indicate Stearns as the stronger player on paper. 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 17, 5:00 AM PDTClaude · Peyton Stearns · 63.0%
Stearns holds a meaningful ranking edge (No. 37, 1316 points vs No. 87, 855 points) and a slightly better win rate (25-22, .532 vs 18-18, .500), plus one title this season to Siniakova's none. Siniakova's ranking trend is sharply negative (55 to 87), while Stearns is essentially stable (36 to 37), suggesting recent results favor Stearns. A ~50-place gap in WTA rankings typically translates to roughly a 60-65% win probability for the higher-ranked player, and Siniakova remains a capable, experienced competitor whose singles record is near even. Surface-specific form, injury status, head-to-head history, travel/fatigue, and market odds are not supplied in this evidence package, so no adjustment for those factors is made.
anthropic/claude-opus-5 · Oct 17, 5:00 AM PDTGemini · Peyton Stearns · 68.0%
Peyton Stearns holds a significant ranking advantage over Katerina Siniakova (37 vs. 87) and has accumulated considerably more ranking points (1316 vs. 855). Stearns also boasts a better season win-loss record (25-22) with one singles title, whereas Siniakova has an even 18-18 record with no titles. Furthermore, Siniakova's recent drop in ranking from 55 to 87 suggests a potential dip in form or loss of points from the previous year. Based on these metrics, Stearns is the clear favorite.
google/gemini-3.1-pro-preview · Oct 17, 5:00 AM PDTGPT · Peyton Stearns · 65.0%
Using only the supplied evidence, Peyton Stearns has the stronger current profile. She is ranked No. 37 versus No. 87 for Katerina Siniakova, a meaningful gap, and her 2026 singles record is better at 25-22 compared with 18-18. Stearns also has more ranking points (1316 vs 855) and one singles title this season versus none. Those facts support Stearns as the favorite, but not overwhelmingly so, because the evidence package is limited to overall rank and season record. Surface form, injuries, head-to-head, travel, and market odds are unavailable when absent, so the estimate should stay moderate rather than aggressive.
openai/gpt-5.4 · Oct 17, 5:00 AM PDTWhat remains uncertain
- Surface-specific form unavailable
- Injuries unavailable
- Head-to-head unavailable
- Travel and scheduling unavailable
- Market odds unavailable
- Surface-specific form not supplied
- Injury/fitness status not supplied
- Head-to-head history not supplied
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- First recorded forecast
First prospective probability state captured for this source and competition.
Record hash
e46ddecc42150f1ec3d0334a794c9247fd71c80fbaecc58b5119b8fcbe4b5298
Reasons are shown as they were recorded. The ledger does not establish that a specific fact caused a probability change.
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