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survival (version 3.1-8)

print.aareg: Print an aareg object

Description

Print out a fit of Aalen's additive regression model

Usage

# S3 method for aareg
print(x, maxtime, test=c("aalen", "nrisk"),scale=1,...)

Arguments

x

the result of a call to the aareg function

maxtime

the upper time point to be used in the test for non-zero slope

test

the weighting to be used in the test for non-zero slope. The default weights are based on the variance of each coefficient, as a function of time. The alternative weight is proportional to the number of subjects still at risk at each time point.

scale

scales the coefficients. For some data sets, the coefficients of the Aalen model will be very small (10-4); this simply multiplies the printed values by a constant, say 1e6, to make the printout easier to read.

for future methods

Value

the calling argument is returned.

Side Effects

the results of the fit are displayed.

Details

The estimated increments in the coefficient estimates can become quite unstable near the end of follow-up, due to the small number of observations still at risk in a data set. Thus, the test for slope will sometimes be more powerful if this last `tail' is excluded.

References

Aalen, O.O. (1989). A linear regression model for the analysis of life times. Statistics in Medicine, 8:907-925.

See Also

aareg