dtl_app_get_alpha_t     Minimum significance level for the final stage
                        under drop-the-losers (DTL) design
dtl_app_get_alpha_t_sim
                        Numerical minimum significance level for the
                        final stage under drop-the-losers (DTL) design
dtl_app_sim             Simulation study for drop-the-losers (DTL)
                        trial.
dtl_app_sim_single      Simulate a single drop-the-losers (DTL) trial.
dtl_cor_the_PH_upper_bound
                        Theoretical upper bound of correlation
                        coefficient between time-to-event primary
                        endpoint and binary surrogate endpoint
dtl_get_alpha_s         Significance level given a fixed correlation
                        coefficient for the final stage under
                        drop-the-losers (DTL) design
dtl_get_alpha_s_sim     Numerical significance level given a fixed
                        correlation coefficient for the final stage
                        under drop-the-losers (DTL) design
dtl_shiny               Shiny app of drop-the-losers (DTL) design
dtl_sim_stat            Generate normal approximated test statistics
                        for drop-the-losers (DTL) design
dtl_tier_sim            Simulated family-wise type I error rate (FWER)
                        given a fixed correlation coefficient under
                        drop-the-losers (DTL) design
dtl_tier_the            Theoretical family-wise type I error rate
                        (FWER) given a fixed correlation coefficient
                        under drop-the-losers (DTL) design
sel_g_func_default      Default arm-select function
