Nk. Neerchal et Jg. Morel, LARGE CLUSTER RESULTS FOR 2 PARAMETRIC MULTINOMIAL EXTRA VARIATION MODELS, Journal of the American Statistical Association, 93(443), 1998, pp. 1078-1087
Two parametric extra variation models are considered. Approximate clos
ed-form expressions are given for the Fisher information matrices. The
expressions are useful in computing maximum likelihood estimates and
obtaining large cluster efficiencies. A simulation study shows that th
e approximations perform very well even in clusters of moderate size.
The models are applied in illustrative examples. A goodness-of-fit tes
t is developed that is applicable even when the cluster sizes are uneq
ual. The null distribution of the test statistic is shown to be well a
pproximated by a chi-squared distribution. For the cluster size config
urations in the examples. the test also has high power in distinguishi
ng between the two models considered. The goodness-of-fit test shows t
hat the new model provides adequate description of the data from the t
hree experiments designed to study induced mutagenic effect.