View source: R/power_comparison_Power_vs_n.R
power_comparison_Power_vs_n | R Documentation |
Compares the power of tests under different sample sizes for the same treatment effect and design through matrices and plots.
power_comparison_Power_vs_n(n_seq, nstart_seq, p, nstop_mat,
replication, group_allo, rho_func_index, rho_func, alpha, sig_level)
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. |
'power_comparison_Power_vs_n' reads different sample sizes as well as the corresponding burn-in size and outputs allocation, estimated rates and powers.
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
## 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
)
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