Var1:
Compute the estimate of the covariance of the statistic in test gLRT1
Description
The function computes the estimate of the covariance of test statistics of the test proposed by Zhao and Sun (2004).
References
Q. Zhao and J. Sun (2004), "Generalized Log-rank Test for Mixed-Censored Failure Time Data", Statistics in Medicine, 23: 1621-1629.