Open Accessimpact of an extreme observation in a paired samples design
Author(s) -
Ben Derrick,
Antonia Broad,
Deirdre Toher,
Paul A. White
Publication year - 2017
Publication title -
metodološki zvezki
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.127
H-Index - 7
eISSN - 1854-0031
pISSN - 1854-0023
DOI - 10.51936/ktch6909
Subject(s) - wilcoxon signed rank test , statistics , mathematics , robustness (evolution) , paired comparison , significant difference , value (mathematics) , student's t test , mann–whitney u test , statistical significance , chemistry , biochemistry , gene
The effect of systematically altering the value of a single observation within a paired differences design is considered. A paradox is observed for the paired samples t-test, where increasing the value of an observation in the direction of the true mean difference results in a higher p-value. Using simulation, deviations from robustness of the paired samples t-test is demonstrated, and is contrasted with Yuen's paired samples t-test and the Wilcoxon signed rank sum test.