You need to read up on the Wilcoxon signed-rank test and the output from wilcox.test!!!
The confidence interval is of the difference of medians, which can certainly be negative. In fact, your estimate is -33, and the confidence interval is (-68, 0) which is reasonable. The value of W is a positive number, in general, and isn't restricted to [0,1] Abhijit On 3/14/2011 11:07 AM, taby gathoni wrote: > my output is as follows: > wilcox.test(main_samp$SCORE~main_samp$GENDER, conf.int = TRUE) > > Wilcoxon rank sum test with continuity correction > > data: main_samp$SCORE by main_samp$GENDER > W = 2780.5, p-value = 0.04829 > alternative hypothesis: true location shift is not equal to 0 > 95 percent confidence interval: > -6.800005e+01 -2.056837e-05 > sample estimates: > difference in location > -33.00003 > result of W seems suspicious since i expect the result to be between 0 and > 1. > > and the confidence intervals are also -ves what could be the challenge? > Thanks Taby > > > > > > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
