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Calculation of the Minimum Significant Difference at the NOEC using a non-parametric test.

Nelly van der Hoeven^*

ECOSTAT, Vondellaan 23, 2332 AA, Leiden, The Netherlands

* Corresponding Author:

Nelly van der Hoeven,
ECOSTAT,
Vondellaan 23,
2332 AA Leiden,
The Netherlands
tel.: (+)31-(0)71-5315011; fax: (+)31-(0)842-116988;
email:

Summary

The Minimum Significant Difference (MSD) at the No Observed Effect Concentration (NOEC) is required in many guidelines for standardised ecotoxicological tests. A method is given to calculate the MSD if non-parametric pair-wise comparison of each concentration with the control is used to determine the NOEC.

keywords: Minimum Significant Difference; Wilcoxon test; NOEC; non-parametric test

Ecotoxicol. Environm. Safety, 70: 61-66, 2007

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Function for the calculation of the Minimum Significant Difference if the significance is tested with the non-parametric Wilcoxon's test, also called the Mann-Whitney-U-test.
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