David Airey wrote:
In Prism 4 (graphpad.com) there is the option of fitting curves using
global curve fitting, in which parameters are shared. This is in a
pharmacology context, like saturation binding. I don't find anything
searching for "global curve fitting" using Stata.
A quick description of global curve fitting in this context is:
http://www.graphpad.com/articles/P4Global.pdf
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You just add another variable to the equation to identify the dataset for each
curve. In the first example given, it's a dummy (indicator) variable: 0 =
control dataset and 1 = treated. In the second example (Schild plot), the
variable is the concentration of antagonist, which naturally occurs in the
nonlinear equation, anyway.
It's the same for the remaining three examples. The curves are fit conjointly,
datasets contributing being identified by indicator or continuous
(concentration) variable terms in the equations.
Joseph Coveney
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