| nodal {boot} | R Documentation |
The nodal data frame has 53 rows and 7 columns.
The treatment strategy for a patient diagnosed with cancer of the prostate depend highly on whether the cancer has spread to the surrounding lymph nodes. It is common to operate on the patient to get samples from the nodes which can then be analysed under a microscope but clearly it would be preferable if an accurate assessment of nodal involvement could be made without surgery.
For a sample of 53 prostate cancer patients, a number of possible predictor variables were measured before surgery. The patients then had surgery to determine nodal involvement. It was required to see if nodal involvement could be accurately predicted from the predictor variables and which ones were most important.
nodal
This data frame contains the following columns:
mA column of ones.
rAn indicator of nodal involvement.
agedThe patients age dichotomized into less than 60 (0) and 60 or over 1.
stageA measurement of the size and position of the tumour observed by palpitation
with the fingers via the rectum. A value of 1 indicates a more serious
case of the cancer.
gradeAnother indicator of the seriousness of the cancer, this one is determined by
a pathology reading of a biopsy taken by needle before surgery.
A value of 1 indicates a more serious case of the cancer.
xrayA third measure of the seriousness of the cancer taken from an X-ray reading.
A value of 1 indicates a more serious case of the cancer.
acidThe level of acid phosphatase in the blood serum.
The data were obtained from
Brown, B.W. (1980) Prediction analysis for binary data. In Biostatistics Casebook. R.G. Miller, B. Efron, B.W. Brown and L.E. Moses (editors), 3–18. John Wiley.
Davison, A.C. and Hinkley, D.V. (1997) Bootstrap Methods and Their Application. Cambridge University Press.