On Fri, 13 Aug 2004, Liaw, Andy wrote: > Before you do any of that, you should realize the fact that simtest does > _not_ do Dunnett's test: It can use `Dunnett' _contrasts_ to do comparisons > with a control, but the actual procedure is different. You are unlikely to > get the same result as other packages that perform standard Dunnett's test > (or Tukey's, for that matter). >
exactly. btw, you don't need to specify the contrast matrix yourself for this type of question: R> summary(simtest(y ~ h)) Simultaneous tests: Dunnett contrasts Call: simtest.formula(formula = y ~ h) Dunnett contrasts for factor h <...> Absolute Error Tolerance: 0.001 Coefficients: Estimate t value Std.Err. p raw p Bonf p adj h11-h1 12.022 -5.272 2.28 0.000 0.000 0.000 h7-h1 11.556 -5.067 2.28 0.000 0.000 0.000 h8-h1 10.952 -4.803 2.28 0.000 0.000 0.000 h2-h1 10.414 -4.567 2.28 0.000 0.000 0.000 h10-h1 10.247 -4.493 2.28 0.000 0.000 0.000 h9-h1 9.494 -4.163 2.28 0.000 0.000 0.000 h3-h1 7.397 -3.244 2.28 0.002 0.006 0.006 h4-h1 5.384 -2.361 2.28 0.020 0.061 0.053 h5-h1 5.085 -2.230 2.28 0.028 0.061 0.053 h6-h1 3.180 -1.394 2.28 0.166 0.166 0.166 does exactly the same because the `type' argument defaults to `Dunnett'. Best, Torsten > Andy > > > From: Laurent Houdusse > > > > Hi! > > > > I use simtest fonction of multcomp package to compile a > > Dunnett's test. > > I have 10 treatments and one control group, so i create a matrix with: > > > > m<-matrix(0,10,11) > > m[1,1]<--1 > > m[1,2]<-1 > > m[2,1]<--1 > > m[2,3]<-1 > > m[3,1]<--1 > > m[3,4]<-1 > > m[4,1]<--1 > > m[4,5]<-1 > > m[5,1]<--1 > > m[5,6]<-1 > > m[6,1]<--1 > > m[6,7]<-1 > > m[7,1]<--1 > > m[7,8]<-1 > > m[8,1]<--1 > > m[8,9]<-1 > > m[9,1]<--1 > > m[9,10]<-1 > > m[10,1]<--1 > > m[10,11]<-1 > > rownames(m)<-c("vehicle+vehicle vs. morphne > > 60mg/kg+vehicle","vehicle+vehicle vs. Naloxone > > 30mg/kg+vehicle","vehicle+vehicle vs. Naloxone 30mg/kg+Morphine > > 60mg/kg","vehicle+vehicle vs. RWJ-69528-000-B > > 0.1mg/kg+vehicle","vehicle+vehicle vs. RWJ-69528-000-B > > 1mg/kg+vehicle","vehicle+vehicle vs. RWJ-69528-000-B 0.1mg/kg+morphine > > 60mg/kg","vehicle+vehicle vs. RWJ-69528-000-B 1mg/kg+morphine > > 60mg/kg","vehicle+vehicle vs. vehicle+acetaminophen > > 600mg/kg","vehicle+vehicle vs. RWJ-69528-000-B 0.1mg/kg+acetaminophen > > 600mg/kg","vehicle+vehicle vs. RWJ-69528-000-B 1mg/kg+acetaminophen > > 600mg/kg") > > y<-c(21.5,14.7,16.7,18.8,17.3,15.527,17.551,17.199,15.895,14.3 > > 88,30,30,30,21 > > .2,14.6,30.83,30.622,30.465,24.563,31.416,30,30,30,30,19.6,17. > > 61,30.346,20.8 > > ,17.045,18.129,17.9,15.4,30,15.9,22.9,31.909,25.633,24.6,20.35 > > 5,18.807,30,18 > > .9,16.4,18.2,22.3,21.3,28.571,17.357,16.983,30.40,26.3,24.4,25 > > ,24.1,14.4,10. > > 256,13.266,29.6,15.344,18.69,30,30,25.7,30,28.5,30,30.32,30,19 > > .879,30.716,25 > > .2,30,30,30,30,30,14.063,28.811,30.396,30.609,30,14.1,30,30,30 > > ,26.322,30.386 > > ,28.583,15.77,29.341,30,17.1,30,30,30,30,20.451,30,23.967,30.5 > > 07,30,30,30,27 > > .7,30,28.5,22.568,32.379,30.374,28.263) > > h<-factor(c(rep(1:11, each = 10))) > > result<-summary(simtest(y ~ h,cmatrix=cbind(0,m))) > > rownames(result$estimate) > > result > > > > > > I want to compare my results with the results obtained with SigmaStat > > Software. > > In my results, i retrieve a correct q' value with the simtest t value > > How can i say if P<0.05 like the SigmStat results? > > Can i use p raw value, p bonf value, p adj value or other to compare > > directly? Or can i use the Dunnett's tables? > > > > Thanks for your help! > > > > > > > > > > Laurent Houdusse > > Analyste Programmeur > > > > ______________________________________________ > > [EMAIL PROTECTED] mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide! > > http://www.R-project.org/posting-guide.html > > > > > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > > ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html