Constrain survival probabilities according to hazards in a lifetable Recalculated constrained survival probabilities (by week) as the lower of the original unadjusted survival probability and the survival implied by the given lifetable (assumed indexed as years).

Usage

constrain_survprob(
  survprob1,
  survprob2 = NA,
  lifetable = NA,
  timevec = 0:(length(survprob1) - 1)
)

Arguments

survprob1: (Unconstrained) survival probability value or vector
survprob2: Optional survival probability value or vector to constrain on (default = NA)
lifetable: Lifetable (default = NA)
timevec: Vector of times corresponding with survival probabilities above

Value

Vector of constrained survival probabilities

Examples

ltable <- tibble::tibble(lttime=0:20, lx=c(1,0.08,0.05,0.03,0.01,rep(0,16)))
survprob <- c(1,0.5,0.4,0.2,0)
constrain_survprob(survprob, lifetable=ltable)
#> [1] 1.0 0.5 0.4 0.2 0.0
timevec <- 100*(0:4)
constrain_survprob(survprob, lifetable=ltable, timevec=timevec)
#> [1] 1.00000000 0.05200139 0.01201389 0.00000000 0.00000000
survprob2 <- c(1,0.45,0.35,0.15,0)
constrain_survprob(survprob, survprob2)
#> [1] 1.00 0.45 0.35 0.15 0.00