The procedure without early acceptance is described in detail in SampleSize.pdf.

The following Mathematica notebooks are available for download:

General Computations for Sample Size Reassessment: Reassess.nb

Sample Size Minimization:

For the procedure

without early acceptance (Minimize over n1): Minimize_n1.nb,

with early acceptance (Minimize over alpha1): Minimize_a1.nb.

For questions please contact Martin Posch.