An Interactive Essay

Signal & Noise

Seven chapters on the math hiding inside every decision you make. Drag the sliders. Watch the numbers move. See what you've been missing.

Seven Chapters

Medical Diagnostics

A test is 95% accurate. It comes back positive. What are the chances you’re actually sick?

Radio Telescope Detection

You’re a SETI analyst. The feed is mostly noise. How do you decide what’s real?

Election Modeling

Your candidate is up 52–48 in the polls. Should you celebrate? That depends on what you mean by ‘up.’

Belief Revision

You start with a hunch. Evidence arrives. How much should your belief shift — and why does the math say less than you think?

Financial Noise

A stock jumped 3% today. Is that a signal worth acting on, or just the market doing what markets do?

Correlated Witnesses

Two eyewitnesses both place the suspect at the scene. That sounds damning — unless they talked to each other first.

One Pattern, Seven Disguises

You’ve seen this equation six times in six disguises. Now watch them all move together.