Crossbook ingests live markets from Kalshi and Polymarket, surfaces the basis between the two venues, and publishes an independent probability estimate for markets I choose. The estimate is called the Take.

Every published Take is written to a public track record and scored with Brier scores and a calibration curve. A call that turned out wrong stays visible next to the ones that turned out right, which is the only arrangement that makes the record worth anything.

A digest goes out on Monday mornings.