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Analyzing designed experiments: Should we report standard deviations or standard errors of the mean or standard errors of the difference or what?

Published online by Cambridge University Press:  20 December 2019

Marcin Kozak Open the ORCID record for Marcin Kozak [Opens in a new window]  and
Hans-Peter Piepho
Marcin Kozak*
Affiliation:
Department of Botany, Warsaw University of Life Sciences – SGGW, Nowoursynowska 159, 02-766 Warsaw, Poland
Hans-Peter Piepho
Affiliation:
Biostatistics Unit, Institute of Crop Science, University of Hohenheim, Fruwirthstr. 23, 70593 Stuttgart, Germany
*
*Corresponding author. Email: nyggus@gmail.com
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Abstract

ANOVA, one of the most common statistical methods applied in agronomy, offers a variety of results we can report when analyzing designed experiments. The focus, of course, is on treatment means, but what should we report to characterize precision? Should we choose treatment standard deviations (SDs) or standard errors of the mean or standard errors of the difference (SEDs)? We discuss why treatment raw SDs should not be reported as the result of ANOVA, and point out that most of the time it is SEDs that should be provided.

Keywords

Standard deviationStandard errorResiduals
Type
Review
Information
Experimental Agriculture , Volume 56 , Issue 2 , April 2020 , pp. 312 - 319
Copyright
© Cambridge University Press 2019

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