Add an example

[graemeleehickey]

Add the Williamson (2008) example

data(epileptic)
epileptic$interaction <- with(epileptic, time * (treat == "LTG"))

longitudinal <- epileptic[, c(1:3, 13)]
survival <- UniqueVariables(epileptic, c(4, 6), "id")
baseline <- UniqueVariables(epileptic, "treat", "id")
data <- jointdata(longitudinal = longitudinal,
                  survival = survival,
                  baseline = baseline,
                  id.col = "id",
                  time.col = "time")
summary(data)

fit <- joint(data = data, long.formula = dose ~ time + treat + interaction,
              surv.formula = Surv(with.time, with.status2) ~ treat,
              longsep = FALSE, survsep = FALSE,
              gpt = 3)

summary(fit)