On approximation of the level probabilities for testing ordered parallel regression lines

✍ Scribed by Gilberto A. Paula

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 363 KB
• Volume: 30
• Category: Article
• ISSN: 0167-7152
• DOI: 10.1016/s0167-7152(95)00236-7

✦ Synopsis

Approximations for the level probabilities in testing order-restricted hypotheses are examined in this paper for generalized linear models with common slope. It is showed, in particular, that the asymptotic null distribution of the likelihood ratio statistic is a mixture of chi-squared distributions for the cases of simple order and simple tree order. Under a balanced structure, the asymptotic null distribution reduces to the well-known chi-bar-squared distribution. The use of the equalweights level probabilities is also investigated. This approximation seems to be satisfactory when the sample sizes and the levels of the covariate are not too different among the strata.