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. Author manuscript; available in PMC: 2013 Mar 7.
Published in final edited form as: Psychol Methods. 2011 Jun;16(2):116–126. doi: 10.1037/a0022657
 n<-111 # (Sample size-1)
 dfM1<-24 # degrees of freedom of M1
 dfM2<-27 # degrees of freedom of M2
 delta<-dfM2*.05ˆ2 # define delta in the alternative hypothesis
 alpha<-.05
 cv<-qchisq(1-alpha,df=dfM2-dfM1) # Critical value under the null hypothesis
 power<-1-pchisq(cv,df=dfM2-dfM1,ncp=n*delta)
 print(power,digits=2)