# Readme

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This is my survival tree program (STREE). It is free to use and
distribute provided that (a) I bear no responsibility as the
consequence of using this program although I welcome collaborations of
using my program for data analysis; (b) the users must acknowledge the
use of this STREE program; and (c) the users are recommended to cite
my book:
H.P. Zhang and B. Singer. (1999) Recursive Partitioning in the
Health Sciences, Springer, New York.
Thanks.
Heping Zhang (December 7, 2000)
sample.dat: This is a sample data file. The first row indicates the
type of covariates. "d" implies deleting that covariate from the
analysis; "o" implies a continuous or an ordinal covariate; "n"
implies a nominal covariate; "r" implies the survival time; and
"c" is for censoring indicator (1=death, 0=alive).
sample.inf: The output file. The file can be read as follows:
Column 1: node number. Node 1 is the root node.
Column 2: number of subjects in the node, e.g., 2418 subjects
in node 2.
Column 3: left daughter node, e.g. node 2 is the left daughter
node of node 1.
Column 4: right daughter node, e.g. node 3 is the right daughter
node of node 1.
Column 5: The splitting variables. For example, variable 1 splits
node 1.
Column 6: The splitting value corresponds to the splitting
variable.
sample.ps: A postscript file for the final tree that can be viewed or
printed. For each node on a tree, median survival time and death
rate are printed. You have to make your own survival curves within
the terminal nodes.
Final notes: I won't be surprised that you might have questions when you
try to use this program. I would appreciate your understanding
for not asking me questions, because this is a freeware.
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