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Research Methods in Weed Science: Statistics

Published online by Cambridge University Press:  20 January 2017

Christian Ritz ,
Andrew R. Kniss  and
Jens C. Streibig
Christian Ritz
Affiliation:
Department of Nutrition, Exercise and Sports, University of Copenhagen, Nørre Allé, DK-2200 Copenhagen N, Denmark
Andrew R. Kniss
Affiliation:
Department of Plant Sciences, University of Wyoming, 3354 1000 E. University Avenue, Laramie, WY 82071
Jens C. Streibig*
Affiliation:
Department of Plant and Environmental Sciences, University of Copenhagen, Hoejbakkegaard, DK-2630 Taastrup, Denmark
*
Corresponding author's E-mail: jcs@plen.ku.dk
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There are various reasons for using statistics, but perhaps the most important is that the biological sciences are empirical sciences. There is always an element of variability that can only be dealt with by applying statistics. Essentially, statistics is a way to summarize the variability of data so that we can confidently say whether there is a difference among treatments or among regression parameters and tell others about the variability of the results. To that end, we must use the most appropriate statistics to get a “correct” picture of the experimental variability, and the best way of doing that is to report the size of the parameters or the means and their associated standard errors or confidence intervals. Simply declaring that the yields were 1 or 2 ton ha−1 does not mean anything without associated standard errors for those yields. Another driving force is that no journal will accept publications without the data having been subjected to some kind of statistical analysis.

Keywords

BromoxynilioxyniloxitrilAnalysis of covarianceanalysis of variancelinear regressionslogistic regressionsnonlinear regressions
Type
Weed Biology and Ecology
Information
Weed Science , Volume 63 , Issue SP1: Special Issue: Research Methods in Weed Science , February 2015 , pp. 166 - 187
Creative Commons
Creative Common License - CCCreative Common License - BYCreative Common License - NCCreative Common License - SA
This is an Open Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike licence (http://creativecommons.org/licenses/by-nc-sa/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the same Creative Commons license is included and the original work is properly cited.
Copyright
Copyright © Weed Science Society of America

References

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