A confidence interval approach to data analysis

Abstract

The objective of ecological experiments is often to determine whether observed effects are large enough to be ecologically important. Despite this, effect size measures and associated measures of precision are frequently missing in published ecological research. In many cases, P-values are the only information available with which to assess the ecological importance of observed effects, but they provide a poor means of assessment. It is argued that specifying an important effect size a priori and then presenting observed effects with their associated confidence intervals is often a more informative way of presenting ecological data. A hypothetical data set is analysed and interpreted using b..