On 27-Apr-2004, Michael Hochster <[EMAIL PROTECTED]> wrote:

> : This isn't a "simple linear regression" problem.  It is a nonlinear
> : regression problem.  There are a number of nonlinear regression programs
> : that can solve your problem for a and b.  Here is such a program that I
> ran
> : through my NLREG program (http://www.nlreg.com)
>
> Yes, it is a simple linear regression problem: ordinary regression
> of y on e^-x. As the author of regression software, you should know
> better.

I agree, by transforming the input variables this function is easily
converted to a linear regression.  But it can be handled more easily and
properly as a nonlienar regression where no transformations are required. 
Remember that fitting a function to a transformed independent variable does
not always yield the same fitting parameter results as fitting the function
to the non-transformed input -- minimizing the sum of squared deviations for
X is not the same as log(X) or sin(X). The difference can be significant.

-- 
Phil Sherrod
(phil.sherrod 'at' sandh.com)
http://www.dtreg.com  (decision tree modeling)
http://www.nlreg.com  (nonlinear regression)
.
.
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