Initial sample size guess for the Potvin methods [Two-Stage / GS Designs]

posted by Helmut Homepage – Vienna, Austria, 2017-08-19 16:06 (1193 d 04:09 ago) – Posting: # 17710
Views: 25,051

Hi ElMaestro,

I tried GetStartNps.X3(GMR=0.95, CV=0.2, Pwr.T=0.8) and was honored with
Error in Power.calc(nps1, GMR, CV, Is.St2 = 1) :
  could not find function "Power.calc"

Can you provide the function Power.calc(), please?

My standard code gives:

GMR              : 0.95
target power     : 0.8
‘best guess’ CV  : 0.2
Fixed sample size: 20
  power          : 0.835
‘Type 1’ TSD, n1 : 16 (80.0% of N)
  ASN            : 20.0
  power (interim): 0.619
  power (final)  : 0.851

How does it compare to yours?

Dif-tor heh smusma 🖖
Helmut Schütz

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