Us vs Them
The mission: make paid prediction markets useless by proving, in public and with a pre-registered method, that a free crowd with nothing at stake forecasts as well as or better than Kalshi and Polymarket. Difference is rival Brier minus crowd Brier: positive means the crowd was better. Sample size next to every number. Published whether we are winning or losing.
Headline
Eligible questions only: at least 20 distinct eligible forecasters at the offset, not voided, not overturned.: nothing resolved yet. The table will fill itself. n=0.
Including questions with fewer than 20 forecasters (not part of the claim).: nothing resolved yet. The table will fill itself. n=0.
Bootstrap confidence intervals appear once n is large enough to mean anything. Until then the raw counts are the whole story.
Recent resolved mirrored questions
Last 50, at the T-24h snapshot. Rival price and crowd median recorded together.
No mirrored question has resolved yet.
The protocol
Pre-registered and public before launch. Reproduced verbatim from the spec.
| Item | Rule |
|---|---|
| Universe | Every Polymarket and Kalshi binary market whose volume at mirror time exceeds MIRROR_MIN_VOLUME (launch value 50,000 USD) and whose close is at least 48 hours after mirror time. Mirrored automatically by cron every 6 hours. No human picks. |
| Snapshots | Rival price and our crowd probability recorded together every hour, and additionally at fixed offsets before close: T-30d, T-7d, T-24h, T-1h. |
| Eligibility per question | Counts at an offset only if our crowd had at least MIN_CROWD_N distinct eligible forecasters at that offset. Questions voided by the rival, or where their resolution was overturned by our dispute process, are reported separately and excluded from the headline. |
| Scores | At each offset: Brier of rival price vs Brier of crowd probability. Over the window: time-averaged Brier of each from mirror time to close. |
| Headline | Wins, losses and ties (difference under 0.005) per offset and for the window average, with pooled mean Brier for each side and a bootstrap 95% confidence interval on the difference. Sample size printed next to every number. |
| Publication | Tally page updated nightly. Full CSV of every forecast (pseudonymous user id, question id, timestamp, probability) and every snapshot, nightly, public, versioned. The About page carries this table verbatim. |
| Commitment | Published whether we are winning or losing. Early numbers at n=30 will probably lose; the story "lost at n=30, won at n=3,000" is worth more than any single number, and hiding a bad tally is the exact behaviour we accuse them of. |
Data
Every forecast and every snapshot, pseudonymous, cached for one hour. Check our work.