## estimate(test-ref) and lsmeans in bear [R for BE/BA]

Dear mittyri,

Very sorry about the delay of this replied message.

» In your example the dataset is balanced.

That's correct.

» The question is how do you obtain LSMeans or what do you output as
» MEAN-ref = 7.32951 » MEAN-test = 7.40146

These two values were simply obtained from mean(LnCmax). So they were geometric means as defined. Since only balanced crossover studies will be analyzed in bear, so lsmeans are the same as arithmetic means.

» » please browse "[link=nk]" for more details (the explanations for the coefficient x32). Does anyone know the name of this coefficient in statistics? Thanks.
» That is called as a contrast.

Ok, thanks a lot. And also I will try your codes later with my test dataset. Your codes show and clarify the differences in calculation of lsmeans and geometric means for an unbalanced crossover study, as well as the contrast is equal to lnPE(I don't know that before!). Please correct me if I do not interpret your codes correctly. Thanks again.

All the best,
-- Yung-jin Lee
bear v2.8.8:- created by Hsin-ya Lee & Yung-jin Lee
Kaohsiung, Taiwan http://pkpd.kmu.edu.tw/bear

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