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Ratkowsky3
Dataset
Additional Information

Dataset
Name:

Rat43

Procedure: Nonlinear Least Squares Regression
Certification Method & Definitions

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

Model: y = f(x;beta) + e  =  (beta(1)) / (1 + exp[beta(2) - beta(3)x])^1/beta(4) + e


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