Berthouex and L. C. Brown:
% _Statistics for Environmental Engineers_, CRC Press, 2002.
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% We fit the Monod model
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% $$ y = \theta_1 \frac{t}{\theta_2 + t} + \epsilon \quad \epsilon\sim N(0,I\sigma^2) $$
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% to observations
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%   x (mg / L COD):  28    55    83    110   138   225   375   
%   y (1 / h):       0.053 0.060 0.112 0.105 0.099 0.122 0.125
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% First clear some variables from possible previous runs.
clear data model options

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% Next, create a data structure for the observations and control