| power_comparison_Power_vs_n {RARfreq} | R Documentation |
Comparison of Powers for Different Tests under Different DBCD Randomization Methods (Binary Responses)
Description
Compares the power of tests under different sample sizes for the same treatment effect and design through matrices and plots.
Usage
power_comparison_Power_vs_n(n_seq, nstart_seq, p, nstop_mat,
replication, group_allo, rho_func_index, rho_func, alpha, sig_level)
Arguments
n_seq |
A sequence of numbers of patients. The default is c(50, 100, 150, 200). |
nstart_seq |
The burn-in sample size of each arm. If NULL, n_seq/20 will be used. |
p |
A vector of probabilities containing probabilities for each treatment arm (where the first element refers to the control arm). The length of p should correspond to the number of treatment arms. The default is p = c(0.3, 0.3, 0.6). |
nstop_mat |
A matrix of sample size stopping caps for each arm. Each row corresponds to each n in n_seq, and each column represents each arm. The trial stops if at least one arm reaches the corresponding cap. The default is NULL, which means no cap. |
replication |
the number of replications of the simulation. The default is 100. |
group_allo |
A number or a vector of group size(s) for allocation. If a number is given, the allocation ratios will be updated for each batch of group_allo samples. If a vector is given, the allocation ratios will be updated sequentially in group according to the vector. The group_allo will be applied to all n (from each n_seq). Any value greater than n will be omitted. The default is group_allo=1, which is the same as group_allo = seq(nstart*length(p)+1,n). |
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 (default) = Rosenberger allocation. |
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. |
sig_level |
Significant level. The default is 0.05. |
Details
'power_comparison_Power_vs_n' reads different sample sizes as well as the corresponding burn-in size and outputs allocation, estimated rates and powers.
Value
Allocation - Average and standard deviation (SD) of allocation distribution
Estimation - Average and standard deviation of the estimators of treatment effect
Power_chisq - Average power of Chi-square test
Power_oneside - Average power of one-sided Welch T-test performed for each of the k-th arm against $H_0: p_1>p_k$ without multiplicity adjustment
Plot - Four figures of results: 1) Allocation mean and SD, 2) Estimated mean response and SD, 3) Power of Chi-square test, 4) Power of one-sided proportion test
Examples
## Default setting
power_comparison_Power_vs_n(
n_seq = seq(from = 50, to = 200, by = 50),
nstart_seq = round(seq(from = 50, to = 200, by = 50) / 20),
p = c(0.3, 0.3, 0.6),
nstop_mat = NULL,
replication = 5,
group_allo = 1,
rho_func_index = 3,
rho_func = NULL,
alpha = 2,
sig_level = 0.05
)