wiki/education/statistics/random-variable.md

title, description, published, date, tags, editor, dateCreated

title	description	published	date	tags	editor	dateCreated
隨機變數 (Random Variable)		true	2025-12-28T17:02:16.122Z		markdown	2025-12-28T16:41:51.938Z

Discrete

Probability Mass Function (PMF)

A set of probability value pi assigned to each of the values taken by the discrete random variables xi.

0 \leq p_i \leq 1 and \sum_{p_i} = 1

Probability P(X = x) = p_i

Cumulative Distribution Function (CDF)

F(X) = P(X \leq x) F(X) = \sum_{y : y \leq x} P(X = y)

Continuous

Probability Density Function (PDF)

Cumulative Distribution Function (CDF)