This classic text and reference has been totally revised, redesigned, and comprehensively updated for the new millennium and beyond—bound in a new, revamped hardcover version. Inside, the reader will find improved coverage of time series analysis by the addition of a treatment of IRIMA models, improved coverage of regression with the addition of consideration of multicollinarity and correlated errors, increased material on Bayesian statistics, and a major section on the use of statistics in hydrologic and water quality modeling; which includes sensitivity analysis, Monte Carlo simulation, First Order Analysis, uncertainty analysis, parameter estimation for models, and calibration and verification of models. A greater emphasis, in this new edition, has been on the use of computers in statistical analysis without the dependence on any one particular software vendor. The reader of this new edition will also notice improved coverage on plotting and graphical analysis and some added coverage of nonparametric terms applicable in hydrology. Exercises follow nearly every chapter for increased retention and learning.