The multidimensional data on community composition, properties of individual populations, or properties of environment are the bread and butter of an ecologist's life. Such data need to be analysed taking into account their multidimensionality. A reductionist approach of looking at the properties of each variable separately does not work in most cases. The methods for statistical analysis of such data sets fit under the umbrella of ‘multivariate statistical methods’.

In this book, we present a consistent set of approaches to answer many of the questions that an ecologist might have about the studied systems. Nevertheless, we happily admit that other quantitative ecologists may approach the same set of questions with a toolbox of methods (partly) different from those presented here. We pay only a limited attention to other, less parametric methods, such as the family of non-metric multidimensional scaling (NMDS) algorithms or the group of methods similar to the Mantel test. We do not want to fuel the sometimes seen controversy between proponents of various approaches to analysing multivariate data. We simply claim that the solutions presented here are not the only ones possible, but they worked for us, as well as for many other researchers.