Bootstrapping Goodness of Fit Statistics in Loglinear Poisson Models

The possible discrepancy between a hypothesized model and the
observed data is measured by so called Goodness of Fit Statistics.
In order to decide whether the observed discrepancy is substantial,
the distributions of these statistics under the hypothesised model
are needed to perform a statistical test. Because of the difficulty
to compute the exact distributions, just when the sample size is
small, better approximations than provided by common asymptotic
theory have to be found. In the case of a loglinear Poisson model
we will do that by different bootstrap methods.