Book Review

by Paul Ganderton

Dytham C. 1999. Choosing and Using Statistics - A Biologist’s Guide. Blackwell Science. pp xi + 218. ISBN 0 86542 653 8. £18.50.

One of the more neglected areas of ecology writing is the production of basic material to guide students through the statistical maze. Quantification is vital and yet it is too often greeted as a chore than an integral part of the ecological process. This book aims to remedy some of the more pressing problems of the statistical tyro. There are the basic assumptions that some form of computer package will be available (usefully, Excel as well as the more obvious MINITAB and SPSS) and that students will not be highly mathematically trained. From these beginnings, Dytham takes the reader through a series of simple steps. The first stage is an introduction to the "8 steps" - a guide to choosing and using the right statistical tests. This is followed by a series of chapters outlining the basic concepts of statistics. Thus chapter 2 focuses on basic terms. Chapter 3 presents a novel and useful technique to selecting the right technique: a key. Familiar to ecologists but put in a new setting this helps get things off to the right start. Chapters on hypotheses, sampling and design; statistics and variables; and descriptive statistics (graphs etc) completes the first part of the book. Subsequent chapters focus on specific groups of tests, how to use them and how to interpret the results. Starting with tests of difference (e.g. Chi-squared, analysis of variance) the author continues with tests of relationships and exploration. Three final chapters are used to clear up a few matters such as statistical symbols, test assumptions and hints/tips.

The whole tone of the book is one of assistance to those who do not have (or need to have) a detailed statistical background to their work. Its technique of grouping tests by function is useful and the key is a great way of selecting the appropriate method. Copious notes for the three statistical packages makes practical work easier. The key is a useful starting point (but some basic knowledge is needed to make the correct choices just as with plant/animal keys). In summary, an excellent text with a refreshing viewpoint.