Confidence Intervals

Inference, estimation, and decision-making from data

A point estimate like x̄ = 5.2 is almost certainly not exactly the true mean, so a single number alone is dishonest. A confidence interval reports a range plus a confidence level: "the true θ lies in [L, U], with 95% confidence." It quantifies how much your finite sample lets you trust the estimate.

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▶ Confidence Intervals
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