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Estimation of an Unknown Dose

Dose-response models are common in agriculture and biology. Dose-response curves are often used in bioassay to determine unknown dosage levels. The programs below illustrate the process of unknown dose estimation under two conditions:

               1) the calibration curve is known without error, and
               2) the calibration curve is estimated with known error.

Examples are given for the Logistic Model:

y = 1/(1 + exp(-B*(dose - G)))


where y = the proportion of sucesses, B is a rate related parameter, G is the estimate of the 50th percentile and dose is the applied dose.

The Bayesian solution reparamterizes the first form in terms of T1, the initial proportion of sucesses at dose = 0, and T2, the final proportion of sucesses at dose = maximum. Prior distributions for T1 and T2 are assumed uniform.

Source

Calibration curve known
Calibration curve estimated

Data

Black Vine Weevil Data