σ Probability & Statistics
Describing data, reasoning about chance, and the difference between a sample and the world.
Assumes: algebra.
| Skill | Mastery | Attempts | Accuracy | To mastery | |
|---|---|---|---|---|---|
| Describing data Mean, median, spread, and when each one lies to you. | Not started | — | — | ~16 | Practise |
| Probability basics Sample spaces, complements, unions, and independence. | Not started | — | — | ~18 | Practise |
| Conditional probability P(A|B), Bayes' theorem, and base rates. After: Probability basics | Not started | — | — | ~28 | Practise |
| Distributions Normal and binomial distributions, and what a standard deviation buys you. After: Describing data, Probability basics | Not started | — | — | ~23 | Practise |
| Sampling and inference Sampling error, confidence intervals, and what a p-value does not mean. After: Distributions | Not started | — | — | ~31 | Practise |
“To mastery” is a planning estimate from the BKT model, not a promise: it assumes you keep answering at the rate the model currently predicts.