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Statistical Assessment of Different Ways of Calculating Land Equivalent Ratios (LER)

Published online by Cambridge University Press:  03 October 2008

B. A. Oyejola  and
R. Mead
B. A. Oyejola
Affiliation:
Department of Applied Statistics, University of Reading, Reading RG6 2AN
R. Mead
Affiliation:
Department of Applied Statistics, University of Reading, Reading RG6 2AN
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Summary

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The use in analysis of variance of six different ways of calculating the Land Equivalent Ratio (LER) was assessed. Criteria used are (1) normality of the residuals of LER values after fitting block and treatment effects, (2) precision of comparisons arising from the analysis of variance, and (3) possible bias in the means. These were examined in detail for data from one experiment and consistency of the results was investigated for seven other sets of data. Separate standardization in each block had no advantages over using the same standardization in all blocks. The use of many different divisors can lead to problems in the statistical analysis of LERs.

Type
Research Article
Information
Experimental Agriculture , Volume 18 , Issue 2 , April 1982 , pp. 125 - 138
Copyright
Copyright © Cambridge University Press 1982

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