[R] [External] Re: [External] Get a result but an error message as well ?

[Jeff Newmiller]

Works for me.

set.seed( 42 )
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() {
  a <- a + rnorm( length( a ), 0, 0.05 )
  b <- b + rnorm( length( b ), 0, 0.05 )
  d <- d + rnorm( length( d ), 0, 0.05 )
  OLS <- lm( a ~ b+d )
  MSE_OLS <- mean( OLS$residuals^2 )
  MSE_OLS
}

my.data <- replicate( 500
                    , my.experiment()
                    )
mean( my.data )


On May 19, 2020 2:30:09 PM PDT, "Richard M. Heiberger" <rmh using temple.edu> wrote:
>you need to pay attention to the intermediate structures that you
>generate.
>If all you want is one number, then that is what you should create
>
>mean(replicate( 500, my.experiment() ))
>
>Since you do seem to want to store the intermediate values, then you
>must
>name
>the object according to its structure.  A one-dimensional vector takes
>names(), not dimnames().
>A two-dimensional structure takes dimnames, and the number of row names
>and
>the number of column
>names must match the number of rows and columns.
>
>
>On Tue, May 19, 2020 at 5:25 PM varin sacha <varinsacha using yahoo.fr>
>wrote:
>
>> 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$residuals^2)
>>
>> return( c(MSE_OLS) )
>> }
>>
>> my.data = replicate( 500, my.experiment() )
>> colnames(my.data) <- c("MSE_OLS")
>> mean(my.data)
>> ########################################
>>
>>
>>
>>
>>
>>
>> Le mardi 19 mai 2020 à 23:14:21 UTC+2, Rui Barradas
><ruipbarradas using sapo.pt>
>> a écrit :
>>
>>
>>
>>
>>
>> Hello,
>>
>> Inline.
>>
>> Às 21:38 de 19/05/20, varin sacha via R-help escreveu:
>> >
>> > Hi Richard,
>> >
>> > Thanks for your response.
>> > However, how can I correct my R code knowing that I want, as a
>result,
>> only one value : the mean of the 500 MSE_OLS values ?
>>
>> Just don't transpose the output of replicate?
>>
>> Hope this helps,
>>
>> Rui Barradas
>>
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > Le mardi 19 mai 2020 à 21:59:07 UTC+2, Richard M. Heiberger <
>> rmh using temple.edu> a écrit :
>> >
>> >
>> >
>> >
>> >
>> >> dim(my.data)
>> > [1]   1 500
>> >
>> > you have a matrix with a single row and 500 columns.
>> > you gave a name to only the first column.
>> >
>> > Look at the result of replicate().  it is a vector.  You transposed
>it
>> into a one-row matrix.
>> >
>> >>   tmp <- replicate( 500, my.experiment() )
>> >> dim(tmp)
>> > NULL
>> >> length(tmp)
>> > [1] 500
>> >> dim(t(tmp))
>> > [1]   1 500
>> >
>> >
>> > On Tue, May 19, 2020 at 3:51 PM varin sacha via R-help <
>> r-help using r-project.org> wrote:
>> >> Dear R-experts,
>> >>
>> >> Here is my R code, I get a result but I also get an error message
>so I
>> doubt I can trust the result I get.
>> >> What is going wrong ? Many thanks.
>> >>
>> >> ########################################
>> >> a<-c(2,4,3,4,6,5,3,1,2,3,4,3,4,5,65)
>> >> b<-c(23,45,32,12,23,43,56,44,33,11,12,54,23,34,54)
>> >> d<-c(9,4,5,3,2,1,3,4,5,6,4,9,10,11,18)
>> >>
>> >> my.experiment <- function( ) {
>> >>
>> >> OLS <- lm( a ~ b+d )
>> >> MSE_OLS<-mean(OLS$residuals^2)
>> >> return( c(MSE_OLS) )
>> >> }
>> >>
>> >> my.data = t(replicate( 500, my.experiment() ))
>> >> colnames(my.data) <- c("MSE_OLS")
>> >> mean(my.data)
>> >> ########################################
>> >>
>> >>
>> >> ______________________________________________
>> >> R-help using 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 using 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.
>> >
>>
>
>	[[alternative HTML version deleted]]
>
>______________________________________________
>R-help using 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.

-- 
Sent from my phone. Please excuse my brevity.