Present in future telecommunication networks are based on digital transmission technology. The transmission channel of these networks can be represented by a cascade composed of a number of elementary channels connected in series. An important step in digital channel modelling is estimation of parameters and distribution functions which characterise the statistical properties of error sequences in the channel. This book presents methods and techniques for parameter (primarily the probability of error) and distribution function (primarily the error gap complementary distribution function) estimation using the error sequences obtained by measurement or simulation in elementary or cascaded channels. The methods and techniques developed are of principal importance in industry and academia when time efficient and reliable methods are required for data processing obtained by measurements or simulation. The wider application of the methods and techniques presented in this book are demonstrated on practical examples related to wideband radio propagation measurement, error correcting codes and digital channel modelling.