Distributions of Quadratic Forms

Abstract

For independent chi-square variables x squared sub m and x squared sub n with m and n degrees of freedom, respectively, we consider the quadratic form where the positive ci are distinct. This paper gives exact finite expressions for the distribution of Q in terms of available functions such as the distribution function of chi-square random variables, modified Bessel Functions, Dawson's integral. These formulas are useful for checking the accuracy of approximations and tables of the distribution of Q and provide a simple alternative in their absence. For large m and n, reasonable approximations to the distribution of Q are available. For the general quadratic form Williams (1984) compares algorithms for truncations of infinite series expansions of the distribution.

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Document Details

Document Type
Technical Report
Publication Date
Nov 24, 1987
Accession Number
ADA190224

Entities

People

  • Herbert Solomon
  • Mary E. Bock

Organizations

  • Stanford University

Tags

Communities of Interest

  • C4I

DTIC Thesaurus Topics

  • Algorithms
  • Bessel Functions
  • Chi Square Test
  • Data Science
  • Distribution Functions
  • Goodness Of Fit Tests
  • Hypergeometric Functions
  • Infinite Series
  • Integrals
  • Military Research
  • Probability
  • Random Variables
  • Statistics
  • Two Dimensional
  • United States
  • United States Government
  • Universities

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Statistical inference.