Re: [R] survey weights
On Sat, 3 Sep 2005, A Das wrote: Hi all, I've been trying to get a large (12mb) Stata survey database into R. I managed that, but when I attach survey weights, something goes wrong. The error message is: object dchina not found. Here's the script: If that is the *first* message then something extremly strange is happening library(car) library(foreign) library(survey) China - read.dta(C:/final07c2.dta) attach(China) This attach() isn't necessary or helpful data(China) You should get a warning here Warning message: data set 'China' not found in: data(China) since China isn't one of the built-in data sets. If you don't get this message it suggests that you do have a built-in dataset called China, which will have overwritten your file. dchina-svydesign(id=~psu,strata=~strata,weights=~weight0x, data=China,nest=TRUE) If this line doesn't produce an error message then a variable called dchina must have been produced, in which case you shouldn't get an error message saying it wasn't found in the next line. summary(dchina) Are you sure there wasn't an earlier error message from the call to svydesign()? -thomas __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] survey weights
Thanks, Thomas. Yes, that's exactly what happened: the warnings came first after data(China), and then after dchina-svydesign... So the design object isn't being produced? The dataset is very large, and the weights were already set in Stata before importing. Would either of those cause problems? -Bobby --- Thomas Lumley [EMAIL PROTECTED] wrote: On Sat, 3 Sep 2005, A Das wrote: Hi all, I've been trying to get a large (12mb) Stata survey database into R. I managed that, but when I attach survey weights, something goes wrong. The error message is: object dchina not found. Here's the script: If that is the *first* message then something extremly strange is happening library(car) library(foreign) library(survey) China - read.dta(C:/final07c2.dta) attach(China) This attach() isn't necessary or helpful data(China) You should get a warning here Warning message: data set 'China' not found in: data(China) since China isn't one of the built-in data sets. If you don't get this message it suggests that you do have a built-in dataset called China, which will have overwritten your file. dchina-svydesign(id=~psu,strata=~strata,weights=~weight0x, data=China,nest=TRUE) If this line doesn't produce an error message then a variable called dchina must have been produced, in which case you shouldn't get an error message saying it wasn't found in the next line. summary(dchina) Are you sure there wasn't an earlier error message from the call to svydesign()? -thomas __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] survey weights
On Sun, 4 Sep 2005, A Das wrote: Thanks, Thomas. Yes, that's exactly what happened: the warnings came first after data(China), and then after dchina-svydesign... So the design object isn't being produced? The dataset is very large, and the weights were already set in Stata before importing. Would either of those cause problems? Probably not. What was the error message from svydesign()? That is what will say what went wrong. -thomas __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] survey weights
Just: missing values in object. That would imply the object was created. But then I write dchina, and it says object dchina not found. -Bobby --- Thomas Lumley [EMAIL PROTECTED] wrote: On Sun, 4 Sep 2005, A Das wrote: Thanks, Thomas. Yes, that's exactly what happened: the warnings came first after data(China), and then after dchina-svydesign... So the design object isn't being produced? The dataset is very large, and the weights were already set in Stata before importing. Would either of those cause problems? Probably not. What was the error message from svydesign()? That is what will say what went wrong. -thomas __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] survey weights
On Sun, 4 Sep 2005, A Das wrote: Just: missing values in object. That would imply the object was created. But then I write dchina, and it says object dchina not found. No, it would not imply the object was created. If it was an error message (rather than a warning) the object would not have been created. I presume the full message was Error in na.fail.default(object) : missing values in object If so, it sounds as though you have missing values in the id, weights, or strata variable. summary(China[,c(psu,stata,weight0x]) will verify this. Stata will just have dropped these observations (use -svydes- to verify this). If you want to drop the observations in R you need to do this explicitly. Having missing data may be unavoidable, but if you have observations in a sample it seems that you should know how they were sampled. To drop these observations you could use obsChina - subset(China, !is.na(psu) !is.na(strata) !is.na(weight0x)) and then use obsChina rather than China in the svydesign() function. -thomas -Bobby --- Thomas Lumley [EMAIL PROTECTED] wrote: On Sun, 4 Sep 2005, A Das wrote: Thanks, Thomas. Yes, that's exactly what happened: the warnings came first after data(China), and then after dchina-svydesign... So the design object isn't being produced? The dataset is very large, and the weights were already set in Stata before importing. Would either of those cause problems? Probably not. What was the error message from svydesign()? That is what will say what went wrong. -thomas Start your day with Yahoo! - make it your home page http://www.yahoo.com/r/hs Thomas Lumley Assoc. Professor, Biostatistics [EMAIL PROTECTED] University of Washington, Seattle __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
Re: [R] survey weights
That worked. Many thanks, Thomas. -Bobby --- Thomas Lumley [EMAIL PROTECTED] wrote: On Sun, 4 Sep 2005, A Das wrote: Just: missing values in object. That would imply the object was created. But then I write dchina, and it says object dchina not found. No, it would not imply the object was created. If it was an error message (rather than a warning) the object would not have been created. I presume the full message was Error in na.fail.default(object) : missing values in object If so, it sounds as though you have missing values in the id, weights, or strata variable. summary(China[,c(psu,stata,weight0x]) will verify this. Stata will just have dropped these observations (use -svydes- to verify this). If you want to drop the observations in R you need to do this explicitly. Having missing data may be unavoidable, but if you have observations in a sample it seems that you should know how they were sampled. To drop these observations you could use obsChina - subset(China, !is.na(psu) !is.na(strata) !is.na(weight0x)) and then use obsChina rather than China in the svydesign() function. -thomas -Bobby --- Thomas Lumley [EMAIL PROTECTED] wrote: On Sun, 4 Sep 2005, A Das wrote: Thanks, Thomas. Yes, that's exactly what happened: the warnings came first after data(China), and then after dchina-svydesign... So the design object isn't being produced? The dataset is very large, and the weights were already set in Stata before importing. Would either of those cause problems? Probably not. What was the error message from svydesign()? That is what will say what went wrong. -thomas Start your day with Yahoo! - make it your home page http://www.yahoo.com/r/hs Thomas Lumley Assoc. Professor, Biostatistics [EMAIL PROTECTED] University of Washington, Seattle __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
