Statistics to support soil research and their interpretation

Much soil research needs statistics to support and confirm impressions and interpretations of investigations in field and laboratory. Many soil scientists have not been trained in statistical method and as a result apply quite elementary techniques out of context and without understanding. This article concentrates on the most common abuses and misunderstandings and points authors to proper use. It distinguishes variance and standard deviation for measuring dispersion from standard error to indicate confidence in estimates of means. It describes the strictly limited context in which to use the coefficient of variation. It stresses the importance of quoting means and differences between them in contrast to statistical significance, which is at best of secondary interest. It guides readers to inspect and explore their data before deciding to transform them for analysis and illustrates what can be achieved by taking logarithms of single variates and by principal component analysis of multivariate data.