Dear Joel, are you trying to apply function mi.t.test from my package MKmisc?
Could you please try: mi.t.test(implist, "pre_test", "post_test", alternative = "greater", paired = TRUE, var.equal = TRUE, conf.level = 0.95) x and y are the names of the variables, not the variables themselves. Best Matthias Am 06.04.2017 um 18:32 schrieb Joel Gagnon:
Dear all, It is my first time posting on this list so forgive me for any rookie mistakes I could make. I want to conduct t-tests on a dataset that has been imputed using the mice package: imput_pps <- mice(pps, m=20, maxit=20, meth='pmm') # pps is my dataset. It contains items from an 11-item questionnaire gather at pre and post test. So the data set has 22 columns. I then proceed to compute the total scores for the pre and post test on my imputed datasets: long_pps <- complete(imput_pps, action ="long", include = TRUE) long_pps$pre_test <- rowSums(long_pps[ ,c(3:13)]) long_pps$post_test <- rowSums(long_pps[ , c(14:24)]) I then used as.mids to convert back to mids object: mids_pps <- as.mids(long_pps) Next, I created an imputation list object using mitools: implist <- lapply(seq(mids_pps$m), function(im) complete(mids_pps, im)) implist <- imputationList(implist) Now, I want to conduct t-tests using the mi.t.test package. I tried the following code: mi.t.test(implist, implist$pre_test, implist$post_test, alternative = "greater", paired = TRUE, var.equal = TRUE, conf.level = 0.95) When I run this code, R tells me that Y is missing. I know this may sound stupid, but I thought that I specified Y with this line: implist$pre_test, implist$post_test - with implist$pre_test being X and implist$post_test being Y - like I usually do for a normal t-test using the t.test function. It seems I don't quite understand what the Y variable is supposed to represent. Could someone help me figure out what I am doing wrong? You help would be very much appreciated. Best regards, Joel Gagnon, Ph.D(c), Department of Psychology, Université du Québec à Trois-Rivières Québec, Canada [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
-- Prof. Dr. Matthias Kohl www.stamats.de ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.