On this Picostat.com statistics page, you will find information about the azprocedure data set which pertains to azprocedure. The azprocedure data set is found in the COUNT R package. You can load the azprocedure data set in R by issuing the following command at the console data("azprocedure"). This will load the data into a variable called azprocedure. If R says the azprocedure data set is not found, you can try installing the package by issuing this command install.packages("COUNT") and then attempt to reload the data. If you need to download R, you can go to the R project website. You can download a CSV (comma separated values) version of the azprocedure R data set. The size of this file is about 82,747 bytes.
Data come from the 1991 Arizona cardiovascular patient files. A subset of the
fields was selected to model the differential length of stay for patients entering
the hospital to receive one of two standard cardiovascular procedures: CABG and PTCA.
CABG is the standard acronym for Coronary Artery Bypass Graft, where the flow of
blood in a diseased or blocked coronary artery or vein has been grafted to bypass
the diseased sections. PTCA, or Percutaneous Transluminal Coronary Angioplasty, is
a method of placing a balloon in a blocked coronary artery to open it to blood flow.
It is a much less severe method of treatment for those having coronary blockage, with
a corresponding reduction in risk.
A data frame with 3589 observations on the following 6 variables.
length of hospital stay
1=Urgent/Emerg; 0=elective (type of admission)
1= Age>75; 0=Age<=75
encrypted facility code (string)
azprocedure is saved as a data frame.
Count models use los as response variable. 0 counts are structurally excluded
1991 Arizona Medpar data, cardiovascular patient files,
National Health Economics & Research Co.
Hilbe, Joseph M (2014), Modeling Count Data, Cambridge University Press
Hilbe, Joseph M (2007, 2011), Negative Binomial Regression, Cambridge University Press
Hilbe, Joseph M (2009), Logistic Regression Models, Chapman & Hall/CRC
library(msme)data(azprocedure)glmazp <- glm(los ~ procedure + sex + admit, family=poisson, data=azprocedure)
exp(coef(glmazp))nb2 <- nbinomial(los ~ procedure + sex + admit, data=azprocedure)
exp(coef(nb2))glmaznb <- glm.nb(los ~ procedure + sex + admit, data=azprocedure)
Dataset imported from https://www.r-project.org.