Home · Unit 3 · Topic 5 · General discrete random variables

General discrete random variables

Determine and use the mean (expected value) of a discrete random variable as a measurement of centre, 𝐸(𝑋) = 𝜇 = ∑ 𝑝𝑖 𝑥𝑖 where 𝑝𝑖 is the probability of outcome 𝑥𝑖 occurring.

mm-u3-t5-s1-d5

Interactive

Expected value as balance point

manipulative

Scrub probability sticks (always a valid pmf) and watch the fulcrum at μ = Σ xᵢ pᵢ — that fulcrum is E(X).

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