Interpreting the results of Friedman test
doerte.apelt at gmx.de wrote:
Hello, Peter Dalgaard wrote:
Not necessarily, but the first suspicion one gets is that what you're doing with Friedman is not equivalent to what you're doing with ANOVA, could you show us the code and data (or an outline of it)?
Please find attached the R script and the data input files. The values in dataForFriedmanTest.dat represent the geometric mean of the values of three repetitions for one observer and one condition. Am I doing something wrong there?
The .R file came as BIN file to me, so r-help may be missing it. Anyways, Friedman's test is a replacement for a two-way ANOVA and you are comparing it to a one-way analysis, and the latter is likely just wrong. Try anova(lm(AUC~as.factor(Condition)+as.factor(Observer),data=dataForANOVA)) or, maybe better summary(aov(AUC ~ as.factor(Condition) + Error(as.factor(Observer) / as.factor(Condition)), data=dataForANOVA))
Thanks in advance Doerte PS: I'm not sure if it is possible to send the dat-files by mail. Therefore I renamed them to *.txt. Please rename back to *.dat.
O__ ---- Peter Dalgaard ?ster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907