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Random number generation for Correlated Survival and Ordinal Outcomes

generate_rv.Rd

This function generates random number vectors of correlated survival and ordinal outcomes. Gaussian or Clayton copula is used to specify the correlation structure. Marginal distributions are based on a exponential distribution. The order outcome is generated by discretizing one of the correlated random numbers based on the quantile.

Usage

generate_rv(
  target_tau,
  num_samples,
  censoring_rate,
  copula_type = c("Gaussian", "Clayton"),
  x_levels = 5,
  x_probs = c("equal", "random"),
  hr = 1
)

Arguments

target_tau

the target value of the Kendall's \(\tau\)

num_samples

the number of simulation samples

censoring_rate

the censoring rate

copula_type

copula type (default = "Gaussian")

  • Gaussian: Gaussian copula

  • Clayton: Clayton copula

x_levels

the number of category for the ordinal outcome (default = 5)

x_probs

the proportion of each level of x

  • equal: equal sample sizes

  • random: random sample sizes

hr

the hazard ratio for survival time (default = 1.0)

Value

  • y: the survival time or censoring time outcome vector

  • event: the event indicator outcome vector

  • x: the ordinal (or continuous) outcome vector

  • t: the true survival time vector (for simulation)

  • c: the true censoring time vector (for simulation)

  • x0: x before discretization (for simulation)

Examples

library(surrosurvo)
set.seed(1234)
data <- generate_rv(0.7, 500, 0.3)
surrosurvo(data$y, data$event, data$x)
#>   method       tau         se       lcl       ucl
#> 1 taumo1 0.6556501 0.08759590 0.4839653 0.8273349
#> 2 taumo2 0.6563674 0.01815766 0.6207791 0.6919558
#> 3   tauo 0.5042325 0.05508774 0.3962625 0.6122024
#> 4  tauso 0.7317075 0.08876159 0.5577379 0.9056770

# 5-level ordinal variable with Clayton copula
data <- generate_rv(0.7, 500, 0.1, copula_type = "Clayton", x_levels = 5)
surrosurvo(data$y, data$event, data$x)
#>   method       tau         se       lcl       ucl
#> 1 taumo1 0.6375091 0.06634978 0.5074659 0.7675522
#> 2 taumo2 0.6376534 0.01635919 0.6055899 0.6697168
#> 3   tauo 0.5999920 0.06012728 0.4821447 0.7178393
#> 4  tauso 0.7182260 0.07404910 0.5730924 0.8633595