exportPattern("^[[:alpha:]]+")
import(numDeriv)
import(survival)
import(MASS)
importFrom("graphics", "abline", "plot", "points", "par", "legend", "text")
importFrom("stats","cov", "nlm", "pchisq", "runif", "integrate",
           "pnorm", "qchisq", "qnorm", "rchisq")
