Re: [R] Dealing with data

2010-08-14 Thread Jonathan Christensen
this helps, > > -- > Gregory (Greg) L. Snow Ph.D. > Statistical Data Center > Intermountain Healthcare > greg.s...@imail.org > 801.408.8111 > > > > -Original Message- > > From: TGS [mailto:cran.questi...@gmail.com] > > Sent: Friday, August 13, 201

Re: [R] Dealing with data

2010-08-13 Thread TGS
, August 13, 2010 1:52 PM > To: Greg Snow > Subject: Re: [R] Dealing with data > > P.S. The degrees of freedom for sprays would be 5 and not 1. > > On Aug 13, 2010, at 12:27 PM, Greg Snow wrote: > > So you want 1 degree of freedom for InsectSprays? You believe that the

Re: [R] Dealing with data

2010-08-13 Thread TGS
Snow > Cc: r-help@r-project.org > Subject: Re: [R] Dealing with data > > # Greg, if R automatically does that then I don't know why it's > treating each indicator > # as a different regressor. In other words, I am interested in treating > 'spray' as one > #

Re: [R] Dealing with data

2010-08-13 Thread Greg Snow
1 AM > To: Greg Snow > Cc: r-help@r-project.org > Subject: Re: [R] Dealing with data > > # Greg, if R automatically does that then I don't know why it's > treating each indicator > # as a different regressor. In other words, I am interested in treating > 'spra

Re: [R] Dealing with data

2010-08-13 Thread TGS
hcare greg.s...@imail.org 801.408.8111 > -Original Message- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of TGS > Sent: Friday, August 13, 2010 11:22 AM > To: David Winsemius > Cc: r-help@r-project.org > Subject: Re: [R] Dea

Re: [R] Dealing with data

2010-08-13 Thread David Winsemius
On Aug 13, 2010, at 1:22 PM, TGS wrote: To clarify, I'd like to create a column of indicators for the respective letters so that I could maybe do regression on indicators, etc. You can just enter that column name in a regression formula. No need to create a separate variable. Try: lm(c

Re: [R] Dealing with data

2010-08-13 Thread Erik Iverson
TGS wrote: To clarify, I'd like to create a column of indicators for the respective letters so that I could maybe do regression on indicators, etc. For instance, "A" gets "1", "B" gets "2", and so on. That's precisely how factors are handled by modeling functions in R! No need to reinvent th

Re: [R] Dealing with data

2010-08-13 Thread Greg Snow
lp-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of TGS > Sent: Friday, August 13, 2010 11:22 AM > To: David Winsemius > Cc: r-help@r-project.org > Subject: Re: [R] Dealing with data > > To clarify, I'd like to create a column of indicators for

Re: [R] Dealing with data

2010-08-13 Thread TGS
To clarify, I'd like to create a column of indicators for the respective letters so that I could maybe do regression on indicators, etc. For instance, "A" gets "1", "B" gets "2", and so on. On Aug 13, 2010, at 10:19 AM, David Winsemius wrote: On Aug 13, 2010, at 1:03 PM, TGS wrote: > # how wo

Re: [R] Dealing with data

2010-08-13 Thread David Winsemius
On Aug 13, 2010, at 1:03 PM, TGS wrote: # how would I code in R to look at the letter of the alphabet # in the second column and create a indicator column for the # corresponding letter? data(InsectSprays) InsectSprays$spray It's already what most people mean when they say "indicator column"