Slippage series

The trade-by-trade record of expected-minus-actual fill across an incubation period, read as a distribution. A small, symmetric, stable series is healthy; one that is systematically one-sided or widening over time is the alarm that the edge may live only in cost assumptions or the venue is drifting.

First used in Lesson 3.4 · Incubation & fill reconciliation — the lesson that makes this term real.