r_simon {VisualizeSimon2Stage}

Random Generator based on Simon's Two-Stage Design

Description

Random generator based on Simon's two-stage design.

Usage

r_simon(R, n1, n, r1, prob)

Arguments

R

positive integer scalar, number of trials R

n1, n

positive integer scalars, Stage-1 sample size n_1 and total sample size n

r1

non-negative integer scalar, number of response in Stage-1 r_1 required exclusively, i.e., passing Stage-1 indicates observing >r_1 responses

prob

double scalar, true response rate p

Details

Function r_simon generates R copies of the number of responses y in the Simon's two-stage design. The conclusion of the trials are,

y \leq r_1

indicates early termination

r_1 < y \leq r

indicates failure to reject H_0

y > r

indicates success to reject H_0

Here r is not needed to generate the random number of responses y. Instead, r is needed to determine if the trial is a failure or a success. Therefore, r is not a parameter in r_simon.

Value

Function r_simon returns an integer vector of length R, which are the R copies of the number of responses in the Simon's two-stage design.

Examples

library(clinfun)
ph2simon(pu = .2, pa = .4, ep1 = .05, ep2 = .1) # using 'Optimal'
# set.seed if needed 
(ys = r_simon(R = 10L, n1 = 19L, n = 54L, r1 = 4L, prob = .3))
table(cut.default(ys, breaks = c(0, 4L, 15L, 54L), right = TRUE,
  labels = c('early-termination', 'fail', 'success')))