Academic Journals Database
Disseminating quality controlled scientific knowledge

Modified Wilcoxon Signed-Rank Test

Author(s): Ikewelugo Cyprian Anaene Oyeka | Godday Uwawunkonye Ebuh

Journal: Open Journal of Statistics
ISSN 2161-718X

Volume: 02;
Issue: 02;
Start page: 172;
Date: 2012;
Original page

Keywords: Proposed Method | Probabilities | Positive | Zero | Tied | Negative | Frequencies

This paper briefly reviews the Wilcoxon signed rank sum test and proposes a modification. Unlike the Wilcoxon method, the proposed approach does not require that the populations being studied be continuous. Also unlike the Wilcoxon signed rank test the proposed method, does not require the absence of zero differences or tied absolute values of differences. Rather the proposed method structurally makes provisions for these possibilities. The proposed test statistic also enables the estimation of the probabilities of positive, zero or tied and negative differences within the data. This was illustrated with an example and the proposed method was generally more efficient and hence more powerful than the Wilcoxon test statistic with the power increasing as the number of tied observations or zero differences increases.
Save time & money - Smart Internet Solutions      Why do you need a reservation system?