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RegisterVIFs? [Design Issues]
posted by Helmut 
– Vienna, Austria, 2013-03-07 16:50 (4058 d 03:32 ago) – Posting: # 10170
Views: 8,817
Hi Simon!
Let’s see which VIFs we get for the same number of samples but with different schedules (IP’s example). Theoretical tmax at 4.837 h.![[image]](img/uploaded/image157.png)
In #1 we have three samples within ±25% of tmax (4, 5, 6 h) and in #2 only two (3.75, 4.75 h). The closest sampling timepoint to the theoretical tmax in #1 is 5 h (+3.37%) and in #2 4.75 h (-1.80%).
If I look at the VIFs for Cmax and tmax I would favor #1.
On the other hand AUC and K10 speak for #2.
BTW, your first plot is a nice example why the linear trapezoidal is such a lousy method.
P.S.: If you upload screenshoots crop / scale down to the maximum size (640px longest side) and save them as 8bit-PNGs in IrfanView. Will look much better than downscaled JPEGs.
Let’s see which VIFs we get for the same number of samples but with different schedules (IP’s example). Theoretical tmax at 4.837 h.
- 0, 0.5, 1, 2, 3, 4, 5, 6, 9, 12, 16, 24, 36, 48, 72 h
- 0, 1, 2, 2.75, 3.75, 4.75, 6.5, 8.75, 11.75, 16, 21.5, 29, 39.25, 53.25, 72 h
In #1 we have three samples within ±25% of tmax (4, 5, 6 h) and in #2 only two (3.75, 4.75 h). The closest sampling timepoint to the theoretical tmax in #1 is 5 h (+3.37%) and in #2 4.75 h (-1.80%).
If I look at the VIFs for Cmax and tmax I would favor #1.
On the other hand AUC and K10 speak for #2.
BTW, your first plot is a nice example why the linear trapezoidal is such a lousy method.
P.S.: If you upload screenshoots crop / scale down to the maximum size (640px longest side) and save them as 8bit-PNGs in IrfanView. Will look much better than downscaled JPEGs.
—
Dif-tor heh smusma 🖖🏼 Довге життя Україна!![[image]](https://static.bebac.at/pics/Blue_and_yellow_ribbon_UA.png)
Helmut Schütz
![[image]](https://static.bebac.at/img/CC by.png)
The quality of responses received is directly proportional to the quality of the question asked. 🚮
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Dif-tor heh smusma 🖖🏼 Довге життя Україна!
Helmut Schütz
The quality of responses received is directly proportional to the quality of the question asked. 🚮
Science Quotes
Complete thread:
- How to Define Sampling Interval eduardojmorales 2006-10-05 21:11 [Design Issues]
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- Sampling (optimization?) SDavis 2013-03-07 10:40
- VIFs?Helmut 2013-03-07 15:50
- Sampling (optimization?) intuitivepharma 2013-03-08 12:39
- Sampling (optimization?) SDavis 2013-03-07 10:40
- Sampling (optimization?) intuitivepharma 2013-03-01 07:42
- Algorithm (geometric progression) eduardojmorales 2006-10-10 18:23
- Soliloquy? H_Rotter 2006-10-06 13:27
- How to Define Sampling Interval eduardojmorales 2006-10-05 23:16
Ing. Helmut Schütz