From: Uwe Ligges <ligges_at_statistik.tu-dortmund.de>

Date: Sat, 08 Mar 2008 21:55:07 +0100

>>> 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?
*

>>> 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_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. Received on Sat 08 Mar 2008 - 21:04:17 GMT

Date: Sat, 08 Mar 2008 21:55:07 +0100

Martin Kaffanke wrote:

> Am Samstag, den 08.03.2008, 19:34 +0100 schrieb Uwe Ligges: >> Martin Kaffanke wrote:

>>> Hi there!

>> >> 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:

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. Received on Sat 08 Mar 2008 - 21:04:17 GMT

Archive maintained by Robert King, hosted by
the discipline of
statistics at the
University of Newcastle,
Australia.

Archive generated by hypermail 2.2.0, at Sat 08 Mar 2008 - 21:30:21 GMT.

*
Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help.
Please read the posting
guide before posting to the list.
*