risksets: Finds the compositions and sizes of risk sets
Description
Focus is on the risk set composition just prior to a failure.
Usage
risksets(x, strata = NULL, max.survs = NULL, members = TRUE)
Arguments
x
A Surv object.
strata
Stratum indicator.
max.survs
Maximum number of survivors in each risk set. If smaller
than the 'natural number', survivors are sampled from the present ones. No
sampling if missing.
members
If TRUE, all members of all risk sets are listed in the
resulting list, see below.
Value
A list with components
antrs
No. of risk sets in each
stratum. The number of strata is given by length(antrs).
risktimes
Ordered distinct failure time points.
eventset
If
'members' is TRUE, a vector of pointers to events in each risk set, else
NULL.
riskset
If 'members' is TRUE, a vector of pointers to the
members of the risk sets, in order. The 'n.events' first are the events. If
'members' is FALSE, 'riskset' is NULL.
size
The sizes of the risk
sets.
n.events
The number of events in each risk set.
sample_fraction
The sampling fraction of survivors in each risk set.
Details
If the input argument max.survs is left alone, all survivors are accounted
for in all risk sets.