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-boun...@r-project.org [mailto:r-help-boun...@r- >> project.org] On Behalf Of Iurie Malai >> Sent: Friday, October 23, 2009 10:46 AM >> To: r-help@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@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@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. ______________________________________________ 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.