Questions and Ambiguities [BE/BA News]

posted by d_labes  – Berlin, Germany, 2011-03-28 14:16 (3394 d 00:57 ago) – Posting: # 6822
Views: 27,756

Dear Helmut,

» Period ratios (second / first administration):
» Type 3: SAS according to R-doc - 2 outliers (#46: 3.524, #45: 26.08)
» Type 5: or is this SAS? - 2 outliers
» Type 6: Minitab, SPSS, Phoenix/WinNonlin - 2 outliers
» ...

SAS has 5 different percentile definitions. The default is:
Let n*p=j+g where j is the integer part, g is the fractional part, n is the number of values, x the ordered values.
Let y denote the percentile. Then (SAS PCTLDEF=5)
  y = 0.5*(xj+xj+1) if g=0
  y = xj           if g>0

This corresponds to R's Type 2 I think.

» Don’t know what to do. :confused: Suggestions?

If the 'outlier' considerations based on the crippled EMA model makes any sense at all, which I'm not convinced at all :no:, I would vote for an analysis of the residuals, not the period ratios also they appeared a natural choice on the first view.
Pro's:Con's:But these Con's are unavoidable because of the EMA 'model', whatever here is modelled.
To add more ambiguities:



Complete thread:

 Admin contact
20,819 posts in 4,356 threads, 1,447 registered users;
online 21 (1 registered, 20 guests [including 13 identified bots]).
Forum time: 15:14 CEST (Europe/Vienna)

Statistics are no substitute for judgment.    Henry Clay

The Bioequivalence and Bioavailability Forum is hosted by
BEBAC Ing. Helmut Schütz