Re: st: transformations in commands

["Brian P. Poi" <bpoi@stata.com>]

> > On 6/2/06, Feiveson, Alan H. (JSC-SK311) <alan.h.feiveson@nasa.gov> wrote:
> > > Hi  - I have been demonstrating the wonders of Stata to users of R and
> > > have been embarrassed by their criticism of  Stata's inability to
> > > transform a variable within the syntax of a command. For example reg y
> > > log(x) won't work. The variable z=log(x) must be generated first. I'm
> > > curious as to whether other statistical software besides R allows this
> > > sort of thing. At any rate, I would strongly urge Stata Corp. to
> > > incorporate this sort flexibility.

One alternative is to use -nl- instead of -regress-:

   . nl (mpg = {b0} + {b1}*log(price))

   . nl (mpg = {c0} + {c1}/weight)

For models linear in the parameters, -nl- will converge in just a couple 
of iterations.


   -- Brian Poi
   -- bpoi@stata.com
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