Cohort

A group of operators measured together for comparison. The unit of comparative analysis.

Operator identifiers + their token pillars + cohort membership.

Cohort-level distributions, percentile ranks, quartiles, IQR fences.

Cohort comparison reveals relative performance — an operator's metrics are only meaningful in the context of a reference cohort.

Compare operator metrics against cohort distributions (medians, quartiles, IQR).

Percentile ranks, z-scores relative to cohort, outlier flags.

If cohort composition does not affect relative rankings, cohort is not a meaningful unit.

Field-analysis schema provides medians, quartiles, and IQR fences for yield, SNR, leverage, velocity.

Cohort selection bias — small cohorts produce unstable percentiles.

SigRank field-analysis methodology, leaderboard percentile computation. Architecture: mos2es.com/architecture.