| backPain {VGAM} | R Documentation |
Data on Back Pain Prognosis, from Anderson (1984)
Description
Data from a study of patients suffering from back pain. Prognostic variables were recorded at presentation and progress was categorised three weeks after treatment.
Usage
data(backPain)
Format
A data frame with 101 observations on the following 4 variables.
- x2
length of previous attack.
- x3
pain change.
- x4
lordosis.
- pain
an ordered factor describing the progress of each patient with levels
worse<same<slight.improvement<moderate.improvement<marked.improvement<complete.relief.
Source
http://ideas.repec.org/c/boc/bocode/s419001.html
The data set and this help file was copied from gnm so that a vignette in VGAM could be run; the analysis is described in Yee (2010).
The data frame backPain2 is a modification of
backPain where the variables have been renamed
(x1 becomes x2,
x2 becomes x3,
x3 becomes x4)
and
converted into factors.
References
Anderson, J. A. (1984). Regression and Ordered Categorical Variables. J. R. Statist. Soc. B, 46(1), 1-30.
Yee, T. W. (2010). The VGAM package for categorical data analysis. Journal of Statistical Software, 32, 1–34. doi:10.18637/jss.v032.i10.
Examples
summary(backPain)
summary(backPain2)