A living atlas of AI evaluation
A model can be 99.9% accurate and catch zero fraud. Real trust is earned one question at a time — from framing the problem to keeping it honest long after it ships.
Question assumptions. Build intuition. Create impact.
Stop asking what a metric means. Start asking where it belongs.
Every metric — accuracy, F1, AUROC, calibration — exists because someone asked a question the last one couldn't answer. Learn the questions, and the metrics finally have a home.
Read the full essay →Ten questions every model must survive
Not one of them is a metric. Metrics are just the tools we use to answer them. A landmark earns its place only if skipping it can sink a model that looks impressive.
What problem are we solving?
Can we trust our data?
What should the model learn?
Is it actually learning?
How well does it perform?
Will it work elsewhere?
Should humans rely on it?
Can we safely deploy it?
Is it still working?
How do we keep improving?
We start with Evaluation
Evaluation is where a model looks most convincing and can mislead you most completely — and it's where all of my writing lives so far. Live now: performance (how 99.9% accuracy can catch zero fraud), ranking (AUROC's false alarms), and calibration (can you trust a 99%?). Next: decision thresholds, and evaluating AI with AI.
Browse the essays on Medium →The series so far — read in order
Traveling with a cat. Every good expedition needs one. He turns up across the atlas — pointing at charts, squinting at confidence scores, occasionally unconvinced. If a figure looks too clean, he's probably already suspicious.
Follow the journey
A new deep dive most weeks — one question at a time. The newsletter is the best way to follow along.