What you are given
- Doses (x): 0.1, 1, 3, 10, 30, 100, 300
- Responses (y): 1, 9.1, 23.1, 50, 75, 90.9, 96.8
Formula: y = D + (A − D) / (1 + (x/C)^B)
Statistics
How do you calculate iC50 / EC50 (4PL fit)?
Fit a dose-response curve and read off the IC50/EC50, Hill slope, and R². The relationship used is y = D + (A − D) / (1 + (x/C)^B).
Worked example
Every number below is computed by the calculator, not typed in
The working
- IC50 / EC50 (C):
inflection=10.005 - Hill slope (B):
slope=0.999 - Asymptotes:
A (low) / D (high)=0.002 / 100.029 - R²:
1 − SS_res/SS_tot=1
IC50 / EC50 = 10.005 (R² 1)
Do it with your own numbers.
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