# Concept derivation guides

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Concept guide



## [Finite joint distribution: validating a joint mass table and aggregating marginals and events from one joint law](/en/derivations/derivation-mko-finite-joint-distribution-01/?from=%2Fen%2Fderivations%2F%3Fq%3Dmko-finite-joint-distribution)

Given the support S={(0,0),(0,1),(1,0),(1,1),(2,1)} with masses p(0,0)=1/6, p(0,1)=1/3, p(1,0)=1/4, p(1,1)=1/12, p(2,1)=1/6, verify that (S,p) is a two-dimensional finite joint distribution; from this one joint law compute the marginals of X and Y, the rectangle event P(X∈{1,2}, Y=1) and the single-pair mass P(X=2, Y=0); finally construct a different joint law with the same marginals, showing that two marginals do not in general determine the joint distribution.

Finite joint distribution

derivation-mko-finite-joint-distribution-01





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