Chi-Squared Distribution

Functions > Statistics > Probability Distributions > Chi-Squared Distribution

Chi-Squared Distribution

The following functions are associated with the chi-squared equation:

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• dchisq(x, d)—Returns the probability density for value x.

• pchisq(x, d)—Returns the cumulative probability distribution for value x.

• qchisq(p, d)—Returns the inverse cumulative probability distribution for probability p.

• rchisq(m, d)—Returns a vector of m random numbers having the chi-squared distribution.

Arguments

• x is a scalar or vector of real values, x ≥ 0. Negative values of x produce a result of zero.

• d is a positive integer representing the degrees of freedom. While the distribution equation is meant to be formulated for integers, you can also use real values.

• Γ is the Gamma function.

• p is a real probability, 0 ≤ p ≤ 1.

• m is an integer, m > 0.