library(MASS)
df<-MASS::anorexia
df$Treat = factor(df$Treat)
library ( hypr )
h <- hypr ( ~ 1/2 * CBT + 1/2 * FT - Cont , ~ CBT - FT , levels = c( "CBT" , "Cont" , "FT" ))
contrasts(df$Treat,how.many=2)<-cmat(h)
model = lm ( Prewt ~ Treat , data = df )
contrasts_summary ( model )
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