ratio = difference of logs! [Regulatives / Guidelines]

posted by Helmut Homepage – Vienna, Austria, 2013-03-11 01:17 (2988 d 21:53 ago) – Posting: # 10181
Views: 18,378

Dear Chirag,

» […] does this apply to the untransformed or Ln transformed data
» The ratios were fine with the Ln transformed data.

Raw data! You need the ln-transformed data only in the BE-statistics. You would have to calculate the difference of logs and backtransform to get % covered. Example:

AUCt 375, AUC 500, covered: 100×375/500=75%.
lnAUCt 5.9269, lnAUC 6.2146, covered: 100×ℯ5.9269–6.2146=75%.

A ratio of logs (95.37%) is nonsense.

Dif-tor heh smusma 🖖
Helmut Schütz

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