Log in
Register'Expected' Power with Fieller [General Statistics]
Dear Martin, dear Helmut!
This behaviour is not unexpected. See the various power curves in:
This has only partly to do with the fact that we use the 'unsymmetrical' acceptance ranges [theta1=0.8, theta2=1/theta1=1.25] ('unsymmetrical' in the original domain):
❝ We recently encountered an unexpected behavior (at least I was not aware of it) with Fieller confidence intervals. It seems that the power for showing equivalence is not maximized at delta = 1 for rather large variances. Is there an error in the code or is this behavior well known?
This behaviour is not unexpected. See the various power curves in:
Hauschke, Steinijans, Pigeot
"Bioequivalence Studies in Drug Development"
Wiley, Chichester (2007)
Chapter 10: Equivalence assessment for clinical endpoints /
10.3 Power and sample size calculation
This has only partly to do with the fact that we use the 'unsymmetrical' acceptance ranges [theta1=0.8, theta2=1/theta1=1.25] ('unsymmetrical' in the original domain):
library(PowerTOST)
power.RatioF(alpha=0.05, theta1=0.8, theta2=1.2, theta0=0.98, CV=0.25, n=20, design="parallel")
theta0 power
0.98 0.123749
1 0.130499
1.01 0.132072
1.02 0.1328319
1.03 0.1321316
1.04 0.1310061—
Regards,
Detlew
Regards,
Detlew
Complete thread:
- Power with Fieller martin 2012-11-15 17:29
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- Power with Fieller Helmut 2012-11-16 01:28
- 'Expected' Power with Fiellerd_labes 2012-11-16 09:03
- 'Expected' Power with Fieller Helmut 2012-11-16 13:54
- 'Expected' Power with Fieller Jack 2012-11-19 10:35
- 'Expected' Power with Fieller Helmut 2012-11-16 13:54
Ing. Helmut Schütz