Probits of Mixtures
- 1 September 1989
- journal article
- research article
- Published by JSTOR in Biometrics
- Vol. 45 (3) , 721-732
- https://doi.org/10.2307/2531679
Abstract
The tolerances of individuals (insects, parasites) in a population have a frequency or probability distribution called a tolerance distribution. Many tolerance distributions in bioassay studies can be the result of a rather heterogeneous population of individuals and can often be modelled as a mixture of a number of standard unimodal distributions. A probit analysis can be generalized to the case where the tolerance distribution is a mixture of location and scale parameter distributions. In this article, the existence and determination of the maximum likelihood estimates are investigated. An expectation-maximization (EM) algorithm for probits of mixtures is developed and it is shown that by application of the EM algorithm, the problem of probits of mixtures can be separated into a series of probits of individual component tolerance distributions.This publication has 1 reference indexed in Scilit:
- The association between frequency of thiabendazole treatment and the development of resistance in field isolates of Ostertagia spp. of sheepInternational Journal for Parasitology, 1984