SAS/R code of MSD method for comparing dissolution [Dissolution / BCS / IVIVC]
Hi,
DDSolver's source is locked, so I thought that, unless authors let you, no one can have a peek as how it works exactly. I have no idea how you figure this out but
from me.
If they obtain low and upper limits as you said then I don't think it's correct. I'm not a statistician so my thinking might be naïve. For me, here the Mahalanobis distance is a measure of the difference in terms of "distance" and when there is no difference the distance would be zero; if there are difference, the distance would always be a positive number. Negative distance?
Couldn't comprehend.
❝ OK, I now know why these values are different.
❝ DDsolver basically calculates the lower and upper bounds as follows:
❝
❝
❝ df <- nt + nr - p - 1
❝ k <- nt * nr / (nt + nr) * df / ((nt + nr - 2) * p)
❝ fcrit <- qf(0.9, p, df)
❝
❝ dm_lower <- dm - sqrt(fcrit/k)
❝ dm_upper <- dm + sqrt(fcrit/k)
❝
❝
❝ That is quite a bit simpler, is it also correct?
DDSolver's source is locked, so I thought that, unless authors let you, no one can have a peek as how it works exactly. I have no idea how you figure this out but

If they obtain low and upper limits as you said then I don't think it's correct. I'm not a statistician so my thinking might be naïve. For me, here the Mahalanobis distance is a measure of the difference in terms of "distance" and when there is no difference the distance would be zero; if there are difference, the distance would always be a positive number. Negative distance?

—
All the best,
Shuanghe
All the best,
Shuanghe
Complete thread:
- SAS/R code of MSD method for comparing dissolution Shuanghe 2014-02-10 17:05 [Dissolution / BCS / IVIVC]
- Wow, what a gem! Helmut 2014-02-10 17:15
- SAS/R code of MSD method for comparing dissolution arjunroy 2014-12-19 10:56
- SAS/R code of MSD method for comparing dissolution Shuanghe 2014-12-19 17:13
- SAS/R code of MSD method for comparing dissolution arjunroy 2014-12-22 05:42
- SAS/R code of MSD method for comparing dissolution Shuanghe 2014-12-24 11:09
- SAS/R code of MSD method for comparing dissolution arjunroy 2014-12-24 11:44
- SAS/R code of MSD method for comparing dissolution Shuanghe 2015-01-08 11:16
- SAS/R code of MSD method for comparing dissolution arjunroy 2014-12-24 11:44
- SAS/R code of MSD method for comparing dissolution Shuanghe 2014-12-24 11:09
- SAS/R code of MSD method for comparing dissolution arjunroy 2014-12-22 05:42
- SAS/R code of MSD method for comparing dissolution Shuanghe 2014-12-19 17:13
- SAS/R code of MSD method for comparing dissolution wligtenberg 2016-12-12 14:09
- SAS/R code of MSD method for comparing dissolution Shuanghe 2016-12-19 19:03
- SAS/R code of MSD method for comparing dissolution wligtenberg 2016-12-20 08:14
- SAS/R code of MSD method for comparing dissolutionShuanghe 2016-12-22 09:23
- SAS/R code of MSD method for comparing dissolution wligtenberg 2016-12-22 11:20
- SAS/R code of MSD method for comparing dissolutionShuanghe 2016-12-22 09:23
- SAS/R code of MSD method for comparing dissolution Olga 2018-04-21 07:01
- SAS/R code of MSD method for comparing dissolution wligtenberg 2016-12-20 08:14
- SAS/R code of MSD method for comparing dissolution Shuanghe 2016-12-19 19:03