This paper studies models in which hypothesis tests have trivial power, that is, power smaller than size. This testing impossibility, or impossibility type A, arises when any alternative is not distinguishable from the null. We also study settings where it is impossible to have almost surely...

The book provides graduate students and researchers with an up-to-date survey of econometric and statistical techniques for the analysis of count data, with a focus on regression models. Specialised discrete data probability models are required in order to interpret results in terms of an...