[R] Wilcoxon Test

[Ivan Calandra]

Try setting the 'correct' argument to FALSE (similar to CORRECT=NO 
option in the SAS documentation).

The p-values are then identical, although the W values are different.

Additionally I cannot understand why you get a warning from R that it 
cannot compute exact p-values because of ties, while the SAS 
documentation states that "Because the sample size is small, the 
large-sample normal approximation might not be adequate, and it is 
appropriate to compute the exact test."
And yet, the p-value from R is identical to the two-sided p-values with 
the normal approximation...?!

Another oddity is the legend of the SAS output, which does not 
correspond to the data in the output itself (but corresponds to the R 
values with correct=TRUE)!

Could the SAS documentation have some errors? I don't have SAS installed 
so cannot test the code.

Ivan

--
Dr. Ivan Calandra
TraCEr, Laboratory for Traceology and Controlled Experiments
MONREPOS Archaeological Research Centre and
Museum for Human Behavioural Evolution
Schloss Monrepos
56567 Neuwied, Germany
+49 (0) 2631 9772-243
https://www.researchgate.net/profile/Ivan_Calandra

On 21/04/2017 14:37, Tripoli Massimiliano wrote:
> Dear R users,
> Why the result of Wilcoxon sum rank test by R is different from sas
>
> https://support.sas.com/documentation/cdl/en/statug/63033/HTML/default/viewer.htm#statug_npar1way_sect022.htm
>
> The code is next:
>
> sampleA <- c(1.94, 1.94, 2.92, 2.92, 2.92, 2.92, 3.27, 3.27, 3.27, 3.27,
>          3.7, 3.7, 3.74)
>
> sampleB <- c(3.27, 3.27, 3.27, 3.7, 3.7, 3.74)
> wilcox.test(A,B,paired = F)
>
>
> Thanks in advance
>
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