Hi Rui, Richard and other, Many thanks for your responses that solve my problem.
Best, SV Le mercredi 20 mai 2020 à 09:09:49 UTC+2, Rui Barradas <ruipbarra...@sapo.pt> a écrit : Hello, I get an error but when running colnames(), not mean(). Notes: 1. I have changed the way the residuals are extracted, if there is a function resid(), the recommended practice is to use it. 2. c("MSE_OLS") and "MSE_OLS" are the identical() objects. Likewise, to return( c(MSE_OLS) ) is to have only MSE_OLS as the last function line. I find the latter clearer. my.experiment <- function() { OLS <- lm(a ~ b + d) #MSE_OLS <- mean(OLS$residuals^2) MSE_OLS <- mean(resid(OLS)^2) MSE_OLS } my.data <- replicate( 500, my.experiment() ) class(my.data) # it's a vector, not a matrix #[1] "numeric" colnames(my.data) <- "MSE_OLS" #Error in `colnames<-`(`*tmp*`, value = "MSE_OLS") : # attempt to set 'colnames' on an object with less than two dimensions mean(my.data) #[1] 105.6951 Hope this helps, Rui Barradas Às 22:25 de 19/05/20, varin sacha escreveu: > Hi Rui, > > If I don't transpose t() the output of the replicate (my R code here below) I > still get an error message !! > > ######################################## > a=c(2,4,3,4,6,5,3,1,2,3,4,3,4,5,65) > b=c(23,45,32,12,23,43,56,44,33,11,12,54,23,34,54) > d=c(9,4,5,3,2,1,3,4,5,6,4,9,10,11,18) > > my.experiment <- function() { > > OLS <- lm( a ~ b+d ) > > MSE_OLS<-mean(OLS$residuals^2) > > return( c(MSE_OLS) ) > } > > my.data = replicate( 500, my.experiment() ) > colnames(my.data) <- c("MSE_OLS") > mean(my.data) > ######################################## > > > > > > > Le mardi 19 mai 2020 à 23:14:21 UTC+2, Rui Barradas <ruipbarra...@sapo.pt> a > écrit : > > > > > > Hello, > > Inline. > > Às 21:38 de 19/05/20, varin sacha via R-help escreveu: >> >> Hi Richard, >> >> Thanks for your response. >> However, how can I correct my R code knowing that I want, as a result, only >> one value : the mean of the 500 MSE_OLS values ? > > Just don't transpose the output of replicate? > > Hope this helps, > > Rui Barradas > >> >> >> >> >> >> >> >> Le mardi 19 mai 2020 à 21:59:07 UTC+2, Richard M. Heiberger >> <r...@temple.edu> a écrit : >> >> >> >> >> >>> dim(my.data) >> [1] 1 500 >> >> you have a matrix with a single row and 500 columns. >> you gave a name to only the first column. >> >> Look at the result of replicate(). it is a vector. You transposed it into >> a one-row matrix. >> >>> tmp <- replicate( 500, my.experiment() ) >>> dim(tmp) >> NULL >>> length(tmp) >> [1] 500 >>> dim(t(tmp)) >> [1] 1 500 >> >> >> On Tue, May 19, 2020 at 3:51 PM varin sacha via R-help >> <r-help@r-project.org> wrote: >>> Dear R-experts, >>> >>> Here is my R code, I get a result but I also get an error message so I >>> doubt I can trust the result I get. >>> What is going wrong ? Many thanks. >>> >>> ######################################## >>> a<-c(2,4,3,4,6,5,3,1,2,3,4,3,4,5,65) >>> b<-c(23,45,32,12,23,43,56,44,33,11,12,54,23,34,54) >>> d<-c(9,4,5,3,2,1,3,4,5,6,4,9,10,11,18) >>> >>> my.experiment <- function( ) { >>> >>> OLS <- lm( a ~ b+d ) >>> MSE_OLS<-mean(OLS$residuals^2) >>> return( c(MSE_OLS) ) >>> } >>> >>> my.data = t(replicate( 500, my.experiment() )) >>> colnames(my.data) <- c("MSE_OLS") >>> mean(my.data) >>> ######################################## >>> >>> >>> ______________________________________________ >>> 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. >>> >> >> ______________________________________________ >> 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. >> ______________________________________________ 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.