NoncentralFRatioDistribution
NoncentralFRatioDistribution[n,m,λ] represents a noncentral F-ratio distribution with n numerator degrees of freedom, m denominator degrees of freedom, and numerator noncentrality parameter λ.
NoncentralFRatioDistribution[n,m,λ, η] represents a doubly noncentral F-ratio distribution with numerator noncentrality parameter λ and denominator noncentrality parameter η.
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