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Troubles with subset()

5 messages · Virgile Capo-Chichi, Milan Bouchet-Valat

Original
Virgile Capo-Chichi
# 
All,
I have the attached dataset which I read from SPSS and transformed a little
bit using the attached script. I am trying to run a logistic regression
using glm() on a subset of my data. When I run the logistic regression on
the whle dataset, it runs OK. As soon as I try to run on the subset, I get
an error message related to different lengths of variables. Any idea why
this might be so? Thanks for your inputs. V
Milan Bouchet-Valat
# 
Le mardi 11 d?cembre 2012 ? 15:09 +0100, Virgile Capo-Chichi a ?crit :
Please paste the code, as it was removed by the server.

Most likely, it comes from the fact that some terms in the formula refer
to variables in the 'data' argument, and some do not.


Regards
Virgile Capo-Chichi
# 
Hello all,

I have the attached dataset which I read from SPSS and transformed a little
bit using the script below. I am trying to run a logistic regression using
glm() on a subset of my data. When I run the logistic regression on the
whle dataset, it runs OK. As soon as I try to run on the subset, I get an
error message related to different lengths of variables. Any idea why this
might be so? Thanks for your inputs. V


Here is my code. Not sure if the data itself got itself through.
=======================
library (foreign)
library (Hmisc)
MC0911_S <- read.spss("C:/Users/samsung/Desktop/R Pilot/MC0911_S.sav",
  use.value.labels=FALSE, max.value.labels=Inf, to.data.frame=TRUE)

colnames(MC0911) <- tolower(colnames(MC0911))

MC0911_S <-transform (MC0911_S, age=2009-a1)
MC0911_S <-transform (MC0911_S, b34=b4/b3)
MC0911_S <-transform (MC0911_S, CCU=b34+b7+b8)
MC0911_S$CCU2 [MC0911_S$CCU==4] <-"1"
MC0911_S$CCU2 [MC0911_S$CCU!=4] <-"0"
MC0911_S$a3<-as.factor(MC0911_S$a3)
MC0911_S$a6<-as.factor(MC0911_S$a6)
MC0911_S$CCU2<-as.numeric(MC0911_S$CCU2)
attach(MC0911_S)
glm(CCU2~age+a3+a6+a8+a9, family=binomial)
detach()
MC0911_2<-subset(MC0911, year>2009)
attach(MC0911_2)
glm(CCU2~age+a3+a6+a8+a9, family=binomial)
detach()


2012/12/11 Milan Bouchet-Valat <nalimilan at club.fr>
Milan Bouchet-Valat
# 
Le mardi 11 d?cembre 2012 ? 17:18 +0100, Virgile Capo-Chichi a ?crit :
This code doesn't work, because the MC0911 object does not exist.

It works fine, though, if I replace all occurrences of MC0911 with
MC0911_S, and CCU2 with ccu2.

The morale of the story is, do not use attach() but pass the data frame
via the 'data' argument to glm(), and when something is weird, close the
R session and start with a clean environment.


Regards
Virgile Capo-Chichi
# 
Trying again with a smaller data file. V




Hello all,

I have the attached dataset which I read from SPSS and transformed a little
bit using the script below. I am trying to run a logistic regression using
glm() on a subset of my data. When I run the logistic regression on the
whle dataset, it runs OK. As soon as I try to run on the subset, I get an
error message related to different lengths of variables. Any idea why this
might be so? Thanks for your inputs. V


Here is my code. Not sure if the data itself got itself through.
=======================
library (foreign)
library (Hmisc)
MC0911_S <- read.spss("C:/Users/samsung/Desktop/R Pilot/MC0911_S.sav",
  use.value.labels=FALSE, max.value.labels=Inf, to.data.frame=TRUE)

colnames(MC0911) <- tolower(colnames(MC0911))

MC0911_S <-transform (MC0911_S, age=2009-a1)
MC0911_S <-transform (MC0911_S, b34=b4/b3)
MC0911_S <-transform (MC0911_S, CCU=b34+b7+b8)
MC0911_S$CCU2 [MC0911_S$CCU==4] <-"1"
MC0911_S$CCU2 [MC0911_S$CCU!=4] <-"0"
MC0911_S$a3<-as.factor(MC0911_S$a3)
MC0911_S$a6<-as.factor(MC0911_S$a6)
MC0911_S$CCU2<-as.numeric(MC0911_S$CCU2)
attach(MC0911_S)
glm(CCU2~age+a3+a6+a8+a9, family=binomial)
detach()
MC0911_2<-subset(MC0911, year>2009)
attach(MC0911_2)
glm(CCU2~age+a3+a6+a8+a9, family=binomial)
detach()



2012/12/11 Milan Bouchet-Valat <nalimilan at club.fr>