Martin Kaffanke wrote: > Am Samstag, den 08.03.2008, 19:34 +0100 schrieb Uwe Ligges: >> Martin Kaffanke wrote: >>> Hi there! >>> >>> I have two little different data. One is a computer test on people, the >>> other is a paper and pencil test. two boxplots show me that the data is >>> almost the same. >>> >>> So now I'd like to know if I could handle all data as one, by testing >>> with ks.test: >>> >>> ==== >>>> ks.test(el$angststoer, fl$angststoer) >>> Two-sample Kolmogorov-Smirnov test >>> >>> data: el$angststoer and fl$angststoer >>> D = 0.1413, p-value = 0.9112 >>> alternative hypothesis: two-sided >>> >>> Warning message: >>> In ks.test(el$angststoer, fl$angststoer) : >>> cannot compute correct p-values with ties >>> ==== >>> >>> Ok, so how can I get the p-value? >> >> You already got it, it is 0.9112, but since you have ties in your data, >> R warns you about it (it's not an error, just a warning). And indeed, >> you have some ties in fl$angststoer. > > Thanks, > But what exactly are ties?
Theory says that there are no ties (german: Bindungen), hence R warns. But with p=0.9, I won't care about that at all. It might be interesting with p close to alpha. In fact, I also would not "handle all data as one", but simply add a factor variable that distinguishes computer from pencil tests so you can inspect it in further analyses... Uwe Ligges > And how can I interpret the answers? (I'm > not sure about the german translation, and the translations don't give > me a hint. > > Thanks, > Martin > >> Uwe Ligges >> >> >> >>> I tried two tests: >>> ==== >>>> ks.test(fl$angststoer, "dnorm") >>> One-sample Kolmogorov-Smirnov test >>> >>> data: fl$angststoer >>> D = 0.8109, p-value < 2.2e-16 >>> alternative hypothesis: two-sided >>> >>> Warning message: >>> In ks.test(fl$angststoer, "dnorm") : >>> cannot compute correct p-values with ties >>> ==== >>> >>> so I see that this message in the first one, depends on fl$angststoer. >>> >>> The I have on this two vectors: >>> >>> ==== >>>> fl$angststoer >>> [1] 1.22184871 -0.30103000 1.00000000 -1.30103000 0.69897000 >>> -0.30103000 >>> [7] -2.30103000 -1.00000000 -2.00000000 0.22184832 -1.77819468 >>> -0.30103000 >>> [13] -2.00000000 -0.30103000 -0.30103000 0.22184832 -0.90308999 >>> -1.14611935 >>> [19] -1.30103000 -3.20411998 -0.60205999 -2.25531594 -3.60205999 >>> -1.30103000 >>> [25] -2.30103000 -0.07918038 -2.14599777 0.74472745 -3.30103000 >>> -0.30103000 >>> [31] -0.30103000 -4.30103000 -0.60205999 -0.14612847 -1.30103000 >>> -1.30103000 >>> [37] 0.00000000 -0.17609234 -0.47711908 -1.77819468 -1.00000000 >>> -1.20411998 >>> [43] -0.07918038 -2.00000000 -2.00000000 -1.30103000 >>>> el$angststoer >>> [1] -2.2407100 -2.8601209 -0.5005659 -2.4007721 -0.3474336 -2.6653452 >>> [7] 0.6548865 -1.6281751 -1.2940679 -0.1316566 -1.4541612 -1.6560206 >>> [13] -0.7441850 0.8219399 0.1746081 -1.2314248 -3.8910969 0.1328448 >>> [19] -1.8439508 -0.8833972 -0.4936052 -0.1664593 -0.8694749 -2.8253588 >>> ==== >>> >>> Doesn't seem to be a problem? >>> >>> What can I do for a good computation? >>> >>> Thanks, >>> Martin >>> >>> >>> >>> >>> >>> ------------------------------------------------------------------------ >>> >>> ______________________________________________ >>> 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.
