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Ratkowsky2
Dataset
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Dataset
Name:

Rat42

Procedure: Nonlinear Least Squares Regression
Certification Method & Definitions

Data: 1 Response Variable (y)
1 Predictor Variable (x)
9 Observations
Higher Level of Difficulty
Observed Data

Model:  y = f(x;beta) + e  =  (beta(1) / (1 + exp[beta(2) - beta(3)x]) + e


This model and data are an example of fitting sigmoidal growth curves taken from Ratkowsky (1983). The response variable is pasture yield, and the predictor variable is growing time.