The notebook — essays & research notes

Essays

A research-and-ideas publication on measurement, learning science, and the translation of both into product. Roughly weekly.

Mastery Measurement Jun 2026 · 2 min · Essay

What mastery measurement actually measures

Most “mastery” dashboards measure compliance with a sequence. The difference between measuring a sequence and measuring a claim changes what you build.

Psychometrics & EDM

Translating IRT for people who build products

May 2026
2 min

Psychometrics & EDM

Bayesian Knowledge Tracing, honestly

Apr 2026
2 min