One, two, three: portable sample size in agricultural research

作者：Hans-Peter Piepho, Doreen Gabriel, Jens Hartung, Andreas Büchse, Meike Grosse, Sabine K. Kurz, Friedrich Laidig, Volker Michel, Iain Proctor, Jan Erik Sedlmeier, Kathrin Toppel, Dörte Wittenburg · 发表于：The Journal of Agricultural Science · 年份：2022 · DOI：10.1017/s0021859622000466 · 被引用次数：25 · 研究领域：Genetics and Plant Breeding、Optimal Experimental Design Methods、Advanced Statistical Methods and Models

Abstract Determination of sample size (the number of replications) is a key step in the design of an observational study or randomized experiment. Statistical procedures for this purpose are readily available. Their treatment in textbooks is often somewhat marginal, however, and frequently the focus is on just one particular method of inference (significance test, confidence interval). Here, we provide a unified review of approaches and explain their close interrelationships, emphasizing that all approaches rely on the standard error of the quantity of interest, most often a pairwise difference of two means. The focus is on methods that are easy to compute, even without a computer. Our main recommendation based on standard errors is summarized as what we call the 1-2-3 rule for a difference of two treatment means.