Deltamatrix computes the Delta matrix, along with maximal
intersection intervals, for a set of intervals.
Usage
Deltamatrix(LR)
Arguments
LR
two-column matrix, each row of which stores an censoring
interval of the form $(L_i, R_i]$. If $L_i =
R_i$, it is an exact observation.
Value
A list consisting of:
leftleft endpoints of the maximal intersection intervals.
rightright endpoints of the maximal intersection intervals.
Deltalogical matrix, for the Delta matrix.
Details
An intersection interval is a nonempty intersection of any combination
of the given intervals, and a maximal intersection interval is an
intersection interval that contains no other intersection interval.
The Delta matrix is a matrix of indicators (TRUE or
FALSE). The rows correspond to the given interval-censored
observations, and the columns the maximal intersection intervals. A
TRUE value of the (i,j)-th element means that the i-th
observation covers the j-th maximal intersection interval, and a
FALSE value the otherwise.
References
Wang, Y. (2008). Dimension-reduced nonparametric maximum likelihood
computation for interval-censored data. Computational
Statistics & Data Analysis, 52, 2388-2402.