This handbook provides quick access to common and specialized probability distributions for modeling practical problems and performing statistical calculations. This second edition enhances the PC calculator StatCalc with electronic help manuals and now contains R functions for cases where StatCalc is not applicable, with the codes available online. This edition also presents major changes in binomial, Poisson, normal, gamma, Weibull, exponential, logistic, Laplace, and Pareto distributions and updates statistical tests and intervals based on recent publications in statistical journals.