The Expert Witness
Ten regression tables enter evidence. The significant one is usually the trap.
The brief
You're the econometrics expert on the stand. One by one, regression tables are entered into evidence, each carrying a causal claim someone badly wants certified — a wage dispute, a policing budget, a drug hearing, a market model. For every exhibit you testify twice: the ruling — uphold the causal claim, find it not proven, or overturn it — and the grounds, the single reason why. The trap is always the same: a small p-value that begs you to call correlation 'cause.' Certify enough junk and the case collapses on appeal; but refuse to certify sound, randomized evidence and you're just an obstruction. It starts with a clean trial. It ends on the landmark case, with a confident opposing expert, a sympathetic story, and a p < 0.001 that everyone in the room wants you to bless.
How you play it
Read the regression table entered into evidence, then give the court your verdict.
The job: Expert Witness — Explaining to a court what a regression does and does not prove — while the other side's expert, with the same data, testifies to the opposite.
What an expert witness actually does →What you're judged on
Every decision is marked to market server-side. These are the meters that move — run one to zero and the simulation ends there.
What it tests
No trivia — the simulation only asks what the chair actually has to know.
Where you learn this
The Expert Witness is the finale of Regression Range, waiting past Level 24 — The Final Exam. You can sit down right now and find out how much of it you already know; the course is there for the parts you don't.
Play Regression Range →Other chairs
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