DBCD_BINARY: Doubly Adaptive Biased Coin Design (Binary Responses)

In RARfreq: Response Adaptive Randomization with 'Frequentist' Approaches

Doubly Adaptive Biased Coin Design (Binary Responses)

Description

Allocates patients to one of treatments based on doubly adaptive biased coin design on summary level data.

Usage

DBCD_BINARY(S_RK, N_RK, group_allo, rho_func_index, rho_func, alpha)

Arguments

S_RK	A vector of current success rates for each treatment arm.
N_RK	A vector of current enrolled subjects in each arm. The length must be the same as 'S_RK'.
group_allo	An integer of the size of group allocation. The default is 1.
rho_func_index	Supply a number of 1, 2 or 3 indicting the allocation function to use. 1 = Wei's allocation; 2 = Neyman allocation; 3 = Rosenberger allocation. The default is 3.
rho_func	Supply a user-specified allocation function of S_RK when rho_func_index is NULL. Default is NULL.
alpha	Supply a number indicating the subscripts of the probability function. The default is 2.

Details

'DBCD_BINARY' assigns the next subject to a group given the observed success rates, enrolled subjects and allocation function.

Value

Number of the arm that the next subject is assigned to.

Examples

# There are 3 arms each of which receives 25 patients.
# The observed response rates are 40%, 28% and 60%, respectively.
# The following command returns the number of arm that the next patient will
# be assigned to.
DBCD_BINARY(S_RK = c(0.4, 0.28, 0.6),
            N_RK = c(25, 25, 25),
            rho_func_index = 3, alpha=2)

# Urn allocation
DBCD_BINARY(S_RK = c(0.4, 0.3),
            N_RK = c(25, 25),
            group_allo = 1,
            rho_func_index = NULL,
            rho_func = function(x) rev(1-x)/sum(1-x),
            alpha=2)

RARfreq documentation built on May 29, 2024, 5:52 a.m.