gehan_poly_estimation {aftsem}R Documentation

Estimation of Regression Parameters from Smoothed Gehan Function

Description

Estimates regression parameters by optimizing a smoothed version of Gehan's statistic.

Usage

gehan_poly_estimation(y, Z, delta, binit, epsilon, optimx.alg, use.grad)

Arguments

y

A numeric vector of the response variable, survival times.

Z

A matrix of covariates.

delta

A censoring indicator vector where 1 indicates an uncensored observation and 0 indicates a censored observation.

binit

Initial values for the beta coefficients.

epsilon

Smoothing parameter.

optimx.alg

Optimalization algorithm that will be used (see optimx package documentation for more information)

use.grad

Indicator wheter numerical or excact gradient will be used, default is FALSE == numerical

Details

The 'gehan_poly_estimation' function performs estimation of regression parameters by minimizing the smoothed Gehan's loss function.

Value

A list containing: - 'BETA': The estimated beta coefficients. - 'RESID': The residuals from the model fit. - 'ITERS': The number of iterations performed during optimization.


[Package aftsem version 1.0 Index]