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Saddlepoint expansions for conditional distributions

Published online by Cambridge University Press:  14 July 2016

Ib M. Skovgaard*
Affiliation:
Royal Veterinary and Agricultural University, Copenhagen
*
Postal address: Royal Veterinary and Agricultural University, Department of Mathematics, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.

Abstract

A saddlepoint expansion is given for conditional probabilities of the form where is an average of n independent bivariate random vectors. A more general version, corresponding to the conditioning on a p – 1-dimensional linear function of a p-dimensional variable is also included. A separate formula is given for the lattice case. The expansion is a generalization of the Lugannani and Rice (1980) formula, which reappears if and are independent. As an example an approximation to the hypergeometric distribution is derived.

Type
Research Papers
Copyright
Copyright © Applied Probability Trust 1987 

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