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Statistics & Probability

Summarise data honestly: mean, median, mode, variance and standard deviation, each computed in the open. Counting principles and combinations feed straight into probability.

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Introductory Sampling and data Populations and samples, kinds of data, how a sample can mislead. mean of 4, 8, 15, 16, 23, 42 Introductory Describing data with graphs Stemplots, histograms, box plots — and the quartiles behind them. median of 3, 1, 4, 1, 5, 9, 2, 6 Introductory Mean, median and mode Centre and spread: mean, median, mode, range, variance, standard deviation. stats 2, 4, 4, 4, 5, 5, 7, 9 Core Probability Events, complements, independence, the addition and multiplication rules. 1/6 * 1/6 Core Counting: permutations and combinations Factorials, ordered and unordered selections. 5 choose 2 Core Discrete random variables Probability distributions, expected value, and the binomial, geometric and Poisson families. 10 choose 3 * (1/2)^3 * (1/2)^7 Core Continuous random variables Density functions: probability is area, and the uniform and exponential distributions. integrate 1/10 dx from 2 to 5 Core The normal distribution The bell curve, z-scores, and the 68–95–99.7 rule. integrate e^(-x^2/2)/sqrt(2*pi) dx from -1 to 1 Core The central limit theorem Why averages are normal: the sampling distribution of the mean. 10/sqrt(25) Core Confidence intervals Estimate ± margin of error, and what “95% confident” actually claims. 50 + 1.96*10/sqrt(100) Core Hypothesis testing Null and alternative hypotheses, test statistics, p-values, and the two kinds of error. (52 - 50)/(10/sqrt(25)) Advanced Comparing two samples Differences of means and proportions, and paired samples. sqrt(4^2/20 + 3^2/25) Advanced Chi-square tests Goodness of fit, independence and homogeneity: comparing observed counts with expected ones. (20-25)^2/25 + (30-25)^2/25 Core Linear regression and correlation The least-squares line, the correlation coefficient, and prediction. line through (1,2) and (3,6) Advanced ANOVA and the F distribution Comparing several means at once by comparing variances. variance of 2, 4, 4, 4, 5, 5, 7, 9

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