As of 2025-08-18, the current leader in Brier score is GPT-5 with 82.21%.
Resolves YES, if an LLM manages to reach over 90% on the leaderboard for at least one week (to prevent lucky outliers).
Resolves NA, if the website stops being maintained for at least one month.
Resolves NO, otherwise.
🏅 Top traders
| # | Trader | Total profit |
|---|---|---|
| 1 | Ṁ339 | |
| 2 | Ṁ279 | |
| 3 | Ṁ46 | |
| 4 | Ṁ42 | |
| 5 | Ṁ36 |
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This is literally impossible.
Unskilled (naive 50:50) is 75%
If you take sports (most frequent event)
60% is brier of 0.16 so 84%
65.35% means predicting half the variance which is near the theoretical limit (since sports are somewhat random with the true Vegas odds usually being between 10 and 90%)
so that’s only half the way from 75% so 87.5%
90% on this scale means questions being asked on Kalshi are 90/10 questions which is quite unlikely
@ChinmayTheMathGuy the concept of the benchmark is cool but the results aren’t that clear / useful
Brier should be -300% to +100%
so 90% means explaining 60% of the variance.

Is this saying every model loses money since they’re all less than 100%
@ChinmayTheMathGuy also
the most risk averse version (gamma = 1)
uses logarithmic utility which is full Kelly which is still too risky for most, fractional Kelly is much better since the bets give some credence to the market.
gamma=2 roughly corresponds to half kelly

@kiudee I think you mean 1 - brier score, which is what they report. a 10% or less brier score (less is better) would mean a 90% or more score on the Prophet Arena