chi-square distribution

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Related to Chi square distribution: Gamma distribution, T distribution, Chi square test

chi-square dis·tri·bu·tion

a variable is said to have a chi-square distribution with K degrees of freedom if it is distributed like the sum of the squares of K independent random variables, each of which has a normal (gaussian) distribution with mean zero and variance one. The chi-square distribution is the basis for many variations of the chi-square(d) test, perhaps the most widely used test for statistical significance in biology and medicine.
References in periodicals archive ?
Since [[chi square].sub.2] (h) obeys an approximate central Chi square distribution of one degree of freedom, the empirical probability and theoretical probability are 0.02 and 0.07, respectively, when [[chi square].sub.2] (h) > 2.71.