The gLRT2
function conducts a k(>=2)-sample test for interval-censored survival data. The test is based on Sun, Zhao, and Zhao (2005). The null hypothesis is that all k survival functions of the failure time are the same, and the alternative hypothesis is that not all functions are the same.
1 2 |
A |
an n by 3 data matrix with the censoring interval of the format (L, R] in columns 1 & 2 and treatmentment indicator ranging from 0 to k-1 in column 3. |
k |
number of treatments. The default is 2. |
rho |
non-negative parameter of the link function used for calculating the test statistics. The default is 0. |
gamma |
non-negative parameter of the link function used for calculating the test statistics. The default is 0. |
EMstep |
a boolean variable indicating whether to take an EM step in the iteration when estimating the common distribution function. The default is TRUE. |
ICMstep |
a boolean variable indicating whether to take an ICM step in the iteration when estimating the common distribution function. The default is TRUE. |
tol |
the maximal L_1 distance between successive estimates before stopping iteration when estimating the commondistribution function. The default is 1.0e-6. |
maxiter |
the maximal number of iterations to perform before stopping when estimating the common distribution function. The default is 1000. |
inf |
value used in data for infinity. The default is Inf. |
Under the null hypothesis, the NPMLE of the common distribution function is computed by function ModifiedEMICM
.
Censoring interval for each observation take the form (L_i, R_i]. No exact observations are allowed, i.e., L_i < R_i.
The chi-square test used in gLRT2
has k-1 degrees of freedom.
The link function used in gLRT2
is ξ(x) = x log(x) x^ρ (1 - x)^γ.
The function returns an object containing the following components:
method |
test procedure used |
u |
the test statistic |
v |
the estimated covariance of the test statistic |
chisq |
the chisquare test statistic |
df |
the degrees of freedom of the test |
p |
p-value of the test |
Qiang Zhao and Jianguo Sun
J. Sun, Q. Zhao, and X. Zhao (2005), "Generalized Log-rank Test for Interval-Censored Data", Scandinavian Journal of Statistics, 32: 45-57.
Q. Zhao (2012), "gLRT - A New R Package for Analyzing Interval-censored Survival Data", Interval-Censored Time-to-Event Data: Methods and Applications, CRC Press, 377-396.
gLRT
, gLRT1
, gLRT3
, gLRT4
, ScoreTest
1 2 |
Questions? Problems? Suggestions? Tweet to @rdrrHQ or email at ian@mutexlabs.com.
Please suggest features or report bugs with the GitHub issue tracker.
All documentation is copyright its authors; we didn't write any of that.