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