crmsens {titecrm} | R Documentation |
Returns an object of class ``homesets'' that summarizes the sensitvity (robustness) of the dose-toxicity model used in the CRM.
crmsens(prior, target, eps=1e-8, maxit=100, incr=0.1, LB=0, UB=Inf, detail=FALSE)
prior |
A vector of initial estimates of toxicity probabilities associated the doses. |
target |
The target DLT rate. |
detail |
If TRUE, the details of the home sets will also be shown. Default is set as FALSE. |
eps |
A control parameter for absolute tolerance. Defaults to `1e-8'. |
maxit |
Maximum number of iterations allowed. Defaults to 100. |
incr |
Step size. Defaults to 0.1. |
LB |
Lower bound of the search space. Defaults to 0. |
UB |
Upper bound of the search space. Defaults to `Inf'. |
Dose-toxicity relationship is assumed as an empiric power model
$a_i^{exp(β)}$ where $a_i$ is the initial estimate of toxicity.
Different choice of the initial probabilities results in various level
of robustness of the CRM, which can be summarized by the indifference
intervals (iint
). See Cheung and Chappell (2002) in the
reference section.
An object of class ``homesets'' is returned, describing the model sensitivity by indifference intervals and a summary statement.
homeset |
The home sets of the model parameter $exp(β)$. |
iint |
The indifference intervals of the dose-toxicity model. |
prior |
Initial estimates of toxicity probabilities. |
target |
The target probability of toxicity at the MTD. |
Cheung, Y. K. and Chappell, R. (2002). A simple technique to evaluate model sensitivity in the continual reassessment method. Biometrics 58:671-674.
# Create a simple data set prior <- c(0.05,0.10,0.20,0.35,0.50,0.70) target <- 0.2 foo <- crmsens(prior,target) print(foo)