R help - Dec 2003 - recode{car} does not work as expected?

Hi to all,

I am having a problem when using recode from the car package. I have
a variable that is char and when I use recode to create a new
variable that is supposed to be numeric I get a factor variable. Here
is the code I am using:
> FCI$PRE1 <- recode (PRE1RES, " c('C', 'c')=1 ; else
= 0 ;
as.factor.result=FALSE ")

So, if I understand correctly the recode command, the line above
should  create FCI$PRE1 variable with 1 if PRE1RES is c and zero
otherwise. However, if I type
> FCI$PRE1[0]
I get as result:

factor(0)
Levels: 0 1

FCI$PRE1 is not a numeric variable, and I get instead a factor.
Recode seems to work fine as it correctly replaces the c's for 1 and
other results for 0, but the fact that the recoded variable is a
factor does not work for me.

Any suggestions on what I am doing wrong?

I am using  R 1.7.1 (2) on a Windows XP machine.

Thanks,

Julie

	[[alternative HTML version deleted]]

Dear Julie,

At 08:57 PM 12/6/2003 -0200, Julie Remold wrote:
>Hi to all,
>
>I am having a problem when using recode from the car package. I have
>a variable that is char and when I use recode to create a new
>variable that is supposed to be numeric I get a factor variable. Here
>is the code I am using:
>
> > FCI$PRE1 <- recode (PRE1RES, " c('C', 'c')=1 ;
else = 0 ;
>as.factor.result=FALSE ")
>
>So, if I understand correctly the recode command, the line above
>should  create FCI$PRE1 variable with 1 if PRE1RES is c and zero
>otherwise. However, if I type
>
> > FCI$PRE1[0]
>
>I get as result:
>
>factor(0)
>Levels: 0 1
>
>FCI$PRE1 is not a numeric variable, and I get instead a factor.
>Recode seems to work fine as it correctly replaces the c's for 1 and
>other results for 0, but the fact that the recoded variable is a
>factor does not work for me.
>
>Any suggestions on what I am doing wrong?
You're putting quotation marks around the argument is.factor.result as if 
it's part of the recode specifications. I believe that you want

         FCI$PRE1 <- recode (PRE1RES, " c('C', 'c')=1 ;
else = 0 ",
as.factor.result=FALSE )

I hope that this helps,
  John

-----------------------------------------------------
John Fox
Department of Sociology
McMaster University
Hamilton, Ontario, Canada L8S 4M4
email: jfox at mcmaster.ca
phone: 905-525-9140x23604
web: www.socsci.mcmaster.ca/jfox