This book has been written to provide a friendly introduction to data analysis and statistical modelling. It covers all the material in a standard introductory course at university, as well as a taste of more advanced topics such as multiple and logistic regression. This fifth edition has been extensively revised to bring key topics such as hypothesis testing much earlier in the text. Randomization tests have also been adopted to support and illuminate traditional algebraic methods. Examples and exercises have been updated throughout and now incorporate connections to the Island, a virtual population to support learning in experimental design, epidemiology and statistical reasoning. However the book still aims to be portable so that it can be easily carried to classes, as well as making handy bedtime reading.