Title: Week 13 — the claim is on trial
Course: Introduction to Statistics (18-Week Generic Edition)

Hi everyone,

Quick scene: Cambridge, the 1920s, afternoon tea. A scientist claims she can taste whether the milk or the tea was poured into the cup first. A statistician at the table doesn't believe her — so he pours eight cups and invents the modern hypothesis test on the spot. She goes eight for eight. Guessing does that about once in seventy tries. Was she guessing?

This week — Hypothesis Testing: Foundations — we build that exact logic: put a claim on trial (the null hypothesis gets the benefit of the doubt), measure how well plain chance could fake your evidence (the p-value), and deliver a verdict with honest language about what it does and doesn't prove. No new formulas — every p-value is handed to you this week. It's all judgment, which is exactly where headlines, ads, and chatbots go wrong.

Three things not to miss: 1. Chapter 13 is your primary reading — the tea story, the courtroom, and the two ways every verdict can be wrong. Start there. 2. Data Lab 13 has you build the null hypothesis with your own hands: 200 sets of 20 coin flips, then you locate a street performer's suspicious 15-of-20 inside your own chance-world. Due at the end of Week 13. 3. Discussion 13 ("The 0.05 Question") puts a claim from your life on trial — initial post two days before the week ends, so classmates have time to reply.

Callback: last week you built confidence intervals — the range of plausible values. A hypothesis test is the same engine pointed at one specific claimed value: is it plausible? Next week the two ideas formally meet, and you'll compute the tests yourself.

Open the Start Here / Module Overview page first — it lays out everything in order with due points. Bring your skepticism (and an opinion about whether eight-for-eight could be luck) to the first session.

See you in the course!