Use, Misuse, and Role of Multiple-Comparison Procedures in Ecological and Agricultural Entomology1

Abstract

Multiple-comparison procedures for comparing means, medians, or proportions are commonly used by entomologists publishing in ecological and agricultural journals of the Entomological Society of America. Unfortunately, there is confusion among many researchers and reviewers with respect to the type I error rates of the various tests. The calculation of and reasoning behind the error rate and relative conservativeness or liberalness of each test are discussed. Several guidelines concerning use of these tests are proposed, including specification of which test was used and why, and a recommendation encouraging a switch to the use of confidence intervals instead of hypothesis tests. It is felt that adoption of these and other proposals for reporting results will increase the meaningfulness and scientific merit of published entomological research.