Title: Week 11 — one number is a bluff (let's build honest ranges)
Course: Introduction to Statistics (18-Week Generic Edition)

Hi everyone,

Quick question: your sleep app says you average 6.9 hours a night. Two decimal places, total confidence. How wrong could it be? It watched a sample of your nights — and last week you learned exactly what sample answers do: they wobble. This week we stop bluffing with single numbers. You'll learn to report the honest version — a confidence interval: the guess, plus or minus a margin, with a confidence you can state and defend.

Three things not to miss: 1. Chapter 11 is your primary reading — it carries the friendly t-table the entire week runs on (three rows, three confidence levels; every problem lands exactly on it). Start there. 2. Data Lab 11 is the term's best two minutes of statistics: everyone draws 10 random penguins and builds a real 95% interval around a knowable truth — then we see whether about 95% of the room captured it. Someone will hold a perfectly-built interval that misses. That's not failure; that's the definition of "95% confident," live. The Discussion ("The Single-Number Bluff") wants your initial post two days before the week ends. 3. Catch your chatbot this week. Ask it for a small-sample interval and odds are it grabs 1.96 where the honest multiplier is 2.262. Your tutorial and lab embed the course's t-table so you can check the machine — the tool drafts, you judge.

One habit to bring: after every interval you build, say the sentence — "we are 95% confident the mean … of all …". The two words "mean" and "all" are where the points (and the honesty) live.

Open the Start Here / Module Overview page first — it lays out everything in order with due points. See you in the course!