blob: 347d846bd6254906b99622237ae2cf168233ca70 [file] [log] [blame]
Dataset Name: Rat43 (Rat43.dat)
File Format: ASCII
Starting Values (lines 41 to 44)
Certified Values (lines 41 to 49)
Data (lines 61 to 75)
Procedure: Nonlinear Least Squares Regression
Description: 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.
Reference: Ratkowsky, D.A. (1983).
Nonlinear Regression Modeling.
New York, NY: Marcel Dekker, pp. 62 and 88.
Data: 1 Response (y = onion bulb dry weight)
1 Predictor (x = growing time)
15 Observations
Higher Level of Difficulty
Observed Data
Model: Exponential Class
4 Parameters (b1 to b4)
y = b1 / ((1+exp[b2-b3*x])**(1/b4)) + e
Starting Values Certified Values
Start 1 Start 2 Parameter Standard Deviation
b1 = 100 700 6.9964151270E+02 1.6302297817E+01
b2 = 10 5 5.2771253025E+00 2.0828735829E+00
b3 = 1 0.75 7.5962938329E-01 1.9566123451E-01
b4 = 1 1.3 1.2792483859E+00 6.8761936385E-01
Residual Sum of Squares: 8.7864049080E+03
Residual Standard Deviation: 2.8262414662E+01
Degrees of Freedom: 9
Number of Observations: 15
Data: y x
16.08E0 1.0E0
33.83E0 2.0E0
65.80E0 3.0E0
97.20E0 4.0E0
191.55E0 5.0E0
326.20E0 6.0E0
386.87E0 7.0E0
520.53E0 8.0E0
590.03E0 9.0E0
651.92E0 10.0E0
724.93E0 11.0E0
699.56E0 12.0E0
689.96E0 13.0E0
637.56E0 14.0E0
717.41E0 15.0E0