Re: [R] Imputing data below detection limit

2012-08-13 Thread Brian S Cade
: [R] Imputing data below detection limit Sent by: r-help-boun...@r-project.org Yes, Jessica, the practice -- of which I also have been and continue to be guilty -- does not really make a lot of sense. It usually doesn't affect estimation all that much, but it can certainly mess up inference

Re: [R] Imputing data below detection limit

2012-08-13 Thread Rich Shepard
On Mon, 13 Aug 2012, Bert Gunter wrote: The proper approach is to use the proper approach: model it as left-censored data. The problem with that is: I'm trying to impute data below detection limit (with multiple detection limits) so i need just a method or a code for imputation and then extra

Re: [R] Imputing data below detection limit

2012-08-13 Thread Bert Gunter
Yes, Jessica, the practice -- of which I also have been and continue to be guilty -- does not really make a lot of sense. It usually doesn't affect estimation all that much, but it can certainly mess up inference. The proper approach is to use the proper approach: model it as left-censored data. Th

Re: [R] Imputing data below detection limit

2012-08-13 Thread Jessica Streicher
Tempting a use of let me google that for you.. Anyway, theres a package called Imputation. I myself used the zoo package. There are probably lots of others since its a real common problem. They usually fill in places in you data that are designated as NA. I do not completely understand what yo

[R] Imputing data below detection limit

2012-08-11 Thread aynumazi
Hello, I'm trying to impute data below detection limit (with multiple detection limits) so i need just a method or a code for imputation and then extract the complete dataset to do the analyses. Is there any package which could do that simply as i'm a beginner in R Thank you -- View this messa

Re: [R] Imputing data

2011-12-02 Thread Weidong Gu
Hi, For imputation using randomForest package, check ?rfImpute Weidong On Fri, Dec 2, 2011 at 6:00 PM, Peter Langfelder wrote: > On Fri, Dec 2, 2011 at 2:16 PM, khlam wrote: >> So I have a very big matrix of about 900 by 400 and there are a couple of NA >> in the list. I have used the followi

Re: [R] Imputing data

2011-12-02 Thread Peter Langfelder
On Fri, Dec 2, 2011 at 2:16 PM, khlam wrote: > So I have a very big matrix of about 900 by 400 and there are a couple of NA > in the list. I have used the following functions to impute the missing data > > data(pc) > pc.na<-pc > pc.roughfix <- na.roughfix(pc.na) > pc.narf <- randomForest(pc.na, na

[R] Imputing data

2011-12-02 Thread khlam
So I have a very big matrix of about 900 by 400 and there are a couple of NA in the list. I have used the following functions to impute the missing data data(pc) pc.na<-pc pc.roughfix <- na.roughfix(pc.na) pc.narf <- randomForest(pc.na, na.action=na.roughfix) yet it does not replace the NA in th