Bioequivalence and Bioavailability Forum • Bear to bear interval with 90% confidence

Bear to bear interval with 90% confidence [🇷 for BE/BA]

posted by yjlee168 – Kaohsiung, Taiwan, 2009-04-01 22:38 (5921 d 15:38 ago) – Posting: # 3447
Views: 12,997

Dear ElMaestro,

❝ The people who write R do it for a reason. For example some of them do not

❝ like SAS. Therefore they don't like LSMeans and type III SS.[...]

You heard that, too. We have been quite frustrated when coding bear and tried to validate obtained results from bear with SAS counterparts. Do you remember that, when we announced bear v1.0, you once suggested that we should have Type III SS output in bear? Then we started getting more information about the differences between SAS and R.

❝ So can we extract LSMeans from an lm fit? No!

❝ Can we in stead extract the difference in LSMeans (test minus R) from an

❝ lm fit? Yes! And this is exactly what we need for the BE evaluation,

❝ because log(LSMean(T)/LSMean(R))=log(LSMean(T)-log(LSMean(R))[...]

Interesting points. Do you mean for unbalanced data or for all kinds here? I don't know this before.

❝ As far as I know the reason has to do with differences in the way model

❝ matrices are specified in R and SAS. I was at some point thinking about

❝ asking a q about this here because I noticed that some model matrices in R

❝ are not full rank. Anyone with insight, please comment!

We maybe need to go to some UseR! Forums to find out.

—
All the best,
-- Yung-jin Lee
bear v2.9.2:- created by Hsin-ya Lee & Yung-jin Lee
Kaohsiung, Taiwan https://www.pkpd168.com/bear
Download link (updated) -> here

Complete thread:

Bear to bear interval with 90% confidence d_labes 2009-04-01 17:00
- Bear to bear interval with 90% confidence ElMaestro 2009-04-01 19:01
  - Bear to bear interval with 90% confidenceyjlee168 2009-04-01 20:38
    - Bear to bear interval with 90% confidence ElMaestro 2009-04-01 21:28
- Bear to bear interval with 90% confidence yjlee168 2009-04-01 20:15
  - Bear to bear interval with 90% confidence ElMaestro 2009-04-01 21:47
    - Bear to bear interval with 90% confidence yjlee168 2009-04-04 23:11
      - Bear to bear interval with 90% confidence ElMaestro 2009-04-05 13:23
        
        Bear to bear interval with 90% confidence yjlee168 2009-04-06 07:50
      - Data set d_labes 2009-04-07 08:46
        
        Data set yjlee168 2009-04-07 13:44
  - Models (not necessarily nice looking young woman) d_labes 2009-04-06 10:49
    - Models (not necessarily nice looking young woman) yjlee168 2009-04-07 14:05