[R] How to apply the Wilcoxon test to a hole table at once?
Iurie Malai
iurie.malai at gmail.com
Sat Oct 24 07:53:20 CEST 2009
Thank you very much!
This is my adapted script and now it is OK:
>lapply(Dataset[3:17], function(x) wilcox.test(x ~ X2,
alternative="two.sided", data=Dataset))
But it is possible to get results more compact, similar to a table?
Iurie Malai
Moldova Pedagogical State University
Steven McKinney wrote:
>
>
>> -----Original Message-----
>> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
>> project.org] On Behalf Of Iurie Malai
>> Sent: Friday, October 23, 2009 10:46 AM
>> To: r-help at r-project.org
>> Subject: [R] How to apply the Wilcoxon test to a hole table at once?
>>
>>
>> Hi,
>>
>> I have a data set:
>>
>> > Dataset
>> X1 X2 X3 X4 X5 X6 X7 X8 X9 X10 X11 X12 X13 X14 X15 X16 X17
>> 1 user1 m 22 19 28 24 12 18 9 7 4 5 4 7 5 7 9
>> 2 user2 f 25 19 23 18 18 15 6 8 6 6 7 10 7 7 7
>> 3 user3 f 28 21 24 18 15 12 10 6 7 9 5 10 5 9 5
>> 4 user4 f 26 19 26 21 12 18 6 6 5 1 3 8 6 5 6
>> 5 user5 m 21 22 26 18 9 6 4 6 1 7 2 4 4 6 4
>> 6 user6 m 24 8 25 12 18 12 7 8 4 1 4 6 7 5 6
>> ...............................................................
>> 71 user71 m 18 4 10 6 3 6 9 5 10 8 4 5 6 5 5
>>
>> I can apply the Wilcoxon test on each column one by one, but how to do
>> this
>> on the hole table at once?
>>
>> > wilcox.test(X3 ~ X2, alternative="two.sided", data=Dataset)
>>
>> Wilcoxon rank sum test with continuity correction
>>
>> data: X3 by X2
>> W = 439, p-value = 0.1291
>> alternative hypothesis: true location shift is not equal to 0
>>
>> >
>
> Here's one way to do it (using airquality dataset)
>
>> lapply(airquality[1:4], function(x) wilcox.test(x ~ Month,
>> alternative="two.sided", data=airquality, subset = Month <= 6))
> $Ozone
>
> Wilcoxon rank sum test with continuity correction
>
> data: x by Month
> W = 82, p-value = 0.1925
> alternative hypothesis: true location shift is not equal to 0
>
>
> $Solar.R
>
> Wilcoxon rank sum test with continuity correction
>
> data: x by Month
> W = 391.5, p-value = 0.8354
> alternative hypothesis: true location shift is not equal to 0
>
>
> $Wind
>
> Wilcoxon rank sum test with continuity correction
>
> data: x by Month
> W = 566, p-value = 0.1461
> alternative hypothesis: true location shift is not equal to 0
>
>
> $Temp
>
> Wilcoxon rank sum test with continuity correction
>
> data: x by Month
> W = 78, p-value = 2.400e-08
> alternative hypothesis: true location shift is not equal to 0
>
>
> Warning messages:
> 1: In wilcox.test.default(x = c(41L, 36L, 12L, 18L, 28L, 23L, 19L, :
> cannot compute exact p-value with ties
> 2: In wilcox.test.default(x = c(190L, 118L, 149L, 313L, 299L, 99L, :
> cannot compute exact p-value with ties
> 3: In wilcox.test.default(x = c(7.4, 8, 12.6, 11.5, 14.3, 14.9, 8.6, :
> cannot compute exact p-value with ties
> 4: In wilcox.test.default(x = c(67L, 72L, 74L, 62L, 56L, 66L, 65L, :
> cannot compute exact p-value with ties
>
> # Sanity check:
>> wilcox.test(Temp ~ Month, alternative="two.sided", data=airquality,
>> subset = Month <= 6)
>
> Wilcoxon rank sum test with continuity correction
>
> data: Temp by Month
> W = 78, p-value = 2.400e-08
> alternative hypothesis: true location shift is not equal to 0
>
> Warning message:
> In wilcox.test.default(x = c(67L, 72L, 74L, 62L, 56L, 66L, 65L, :
> cannot compute exact p-value with ties
>>
> # Same as lapply loop result
>
>
> HTH
>
> Steven McKinney
> Statistician
> Molecular Oncology and Breast Cancer Program
> British Columbia Cancer Research Centre
>
>
>
>
>
>>
>> I researched on this, but I can't find a solution.
>> I would really appreciate any help.
>>
>> P.S. Excuse my lack of terminology :).
>>
>> Iurie Malai
>> Moldova Pedagogical State University
>> --
>> View this message in context: http://www.nabble.com/How-to-apply-the-
>> Wilcoxon-test-to-a-hole-table-at-once--tp26030572p26030572.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
>> ______________________________________________
>> R-help at 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.
>
> ______________________________________________
> R-help at 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.
>
>
--
View this message in context: http://www.nabble.com/How-to-apply-the-Wilcoxon-test-to-a-hole-table-at-once--tp26030572p26036377.html
Sent from the R help mailing list archive at Nabble.com.
More information about the R-help
mailing list