Although it has been substantially updated and revised, this newedition follows the same easy-to-read pattern of the first edition. The introductory material on estimation and hypothesis testing has been rewritten to highlight modern approaches as well giving timely warning against potential misuse. New material covers ethical considerations in experimentation, discussion of the relationship between power and sample size, analysis of directional data, measures of agreement, an introduction to capture-recapture methodology in fields ranging fields ranging from ecology to medicine.