## Bernoulli

• Bernoulli
• Volume 12, Number 3 (2006), 491-500.

### Saddlepoint approximation in exponential models with boundary points

#### Abstract

A saddlepoint approximation is developed for the likelihood ratio test statistic in non-regular exponential models. For the one-parameter case, it is proved that the saddlepoint correction has a relative error of order $O ( n - 1 )$, assuming that the canonical statistic has four finite moments. The results are applied in reliability theory and survival analysis, testing for exponentiality. Note that we are using the saddlepoint method for statistics without moment generating function.

#### Article information

Source
Bernoulli, Volume 12, Number 3 (2006), 491-500.

Dates
First available in Project Euclid: 28 June 2006

https://projecteuclid.org/euclid.bj/1151525132

Digital Object Identifier
doi:10.3150/bj/1151525132

Mathematical Reviews number (MathSciNet)
MR2232728

Zentralblatt MATH identifier
1100.62016

#### Citation

Del Castillo, Joan; López-Ratera, Anna. Saddlepoint approximation in exponential models with boundary points. Bernoulli 12 (2006), no. 3, 491--500. doi:10.3150/bj/1151525132. https://projecteuclid.org/euclid.bj/1151525132

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