fCERNewBound: Compute new stage-wise bounds after adaptation

In lrstat: Power and Sample Size Calculation for Non-Proportional Hazards and Beyond

Compute new stage-wise bounds after adaptation

Description

Compute new stage 2 bounds after an adaptation of the hypotheses tested or their weights.

Usage

fCERNewBound(
  stg1_p,
  wgtmat,
  family = NULL,
  corr = NULL,
  stg1_inthyp_nr_idx,
  CER,
  stg2_elemhyp_idx,
  stg2_wgtmat,
  info_frac_new,
  nthreads = 0
)

Arguments

stg1_p	P-values for the elementary hypotheses in stage 1.
wgtmat	Weight matrix for the original intersection hypotheses.
family	Family matrix indicating which hypotheses belong to which families. If NULL, all hypotheses are assumed to belong to the same family.
corr	Correlation matrix for the test statistics.
stg1_inthyp_nr_idx	Indices of the intersection hypotheses not rejected in stage 1.
CER	Conditional error rates for the intersection hypotheses.
stg2_elemhyp_idx	Indices of the elementary hypotheses in stage 2.
stg2_wgtmat	Weight matrix for the intersection hypotheses in stage 2.
info_frac_new	New information fraction for stage 1 after adaptation.
nthreads	The number of threads to use in simulations (0 means the default RcppParallel behavior).

Value

A list containing:

• inthyp: The indicator matrix of the adapted intersection hypotheses.

• stg2_coef_new: The new stage 2 coefficient for each adapted intersection hypothesis.

• stg2_bnd_new: The new stage 2 bounds for the elementary hypotheses in each adapted intersection hypothesis.

Author(s)

Kaifeng Lu, [e-mail]

References

Cyrus Mehta, Ajoy Mukhopadhyay, and Martin Posch. Graph Based, Adaptive, Multiarm, Multiple Endpoint, Two-Stage Designs. Statistics in Medicine. 2025.

Examples

initial_weights <- c(0.5, 0.5, 0, 0)
transition_matrix <- matrix(c(0, 0.5, 0.5, 0,
                              0.5, 0, 0, 0.5,
                              0, 1, 0, 0,
                              1, 0, 0, 0),
                            nrow = 4, byrow = TRUE)
wgtmat <- fwgtmat(initial_weights, transition_matrix)
family <- matrix(c(1, 1, 0, 0,
                   0, 0, 1, 1),
                 nrow = 2, byrow = TRUE)
corr <- matrix(c(1, 0.5, NA, NA,
                 0.5, 1, NA, NA,
                 NA, NA, 1, 0.5,
                 NA, NA, 0.5, 1),
               nrow = 4, byrow = TRUE)
stage1_pvalues <- c(0.00045, 0.0952, 0.0225, 0.1104)
bounds <- fCERStageBound(
  wgtmat, family, corr, alpha = 0.025,
  alpha1 = errorSpent(0.5, 0.025, "sfOF"),
  info_frac = 0.5, nthreads = 1)
conditional_error_rates <- fCERCer(
  stage1_pvalues, wgtmat, family, corr, info_frac = 0.5,
  bounds$stg1_bnd, bounds$stg2_bnd, nthreads = 1)
stage2_weight_matrix <- fwgtmat(
  w = c(0.5, 0.5),
  G = matrix(c(0, 1, 1, 0), 2, 2, byrow = TRUE))
fCERNewBound(stage1_pvalues, wgtmat, family, corr,
             conditional_error_rates$stg1_inthyp_nr_idx,
             conditional_error_rates$CER,
             stg2_elemhyp_idx = c(2, 4),
             stage2_weight_matrix, info_frac_new = 0.4,
             nthreads = 1)

lrstat documentation built on Aug. 25, 2026, 5:07 p.m.