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Re: REGRESS Question [message #32058 is a reply to message #31982]

Thu, 05 September 2002 11:31

julia[1]
Messages: 1
Registered: September 2002

Junior Member

David --

I ran into problems with the regress routine a few years ago, trying
to regress large amounts of data. The problem is that regress.pro
calls the total routine, which is called in floating point precision.
I had more obvious problems than the 2% difference in goodness of fit
that your reporting, but I found I had to modify regress.pro to call
total in double precision.

Julia

David Fanning <david@dfanning.com> wrote in message news:<MPG.17e027561a59e932989994@news.frii.com>...
> Folks,
>
> I have a client who has asked me to create a pixel density
> function between two images and then perform a regression
> analysis on the resulting distribution. No problem doing all
> this, but she finds that the results of my regression analysis
> differ from the same analysis performed in other statistics
> packages. In fact, three different packages give the same
> answer, and then there is IDL. :-(
>
> For example, if the other packages calculate a "goodness
> of fit" of 0.95, IDL might report 0.97.
>
> Here is my question. Are there any known problems with REGRESS?
> Or, can I assume that this problem comes from my own mathematical
> ignorance?
>
> Cheers,
>
> David

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[Message index]

		REGRESS Question By: David Fanning on Wed, 04 September 2002 14:21
		Re: REGRESS Question By: Mike Alport on Fri, 06 September 2002 00:26
		Re: REGRESS Question By: julia[1] on Thu, 05 September 2002 11:31
		Re: REGRESS Question By: William Clodius on Thu, 05 September 2002 10:31
		Re: REGRESS Question By: justspam03 on Wed, 22 October 2003 07:01
		Re: REGRESS Question By: wmconnolley on Wed, 22 October 2003 06:03
		Re: REGRESS Question By: Chris Lee on Wed, 22 October 2003 03:44
		Re: regress question By: Wout De Nolf on Mon, 01 December 2008 00:38
		Re: regress question By: mccreigh on Sun, 30 November 2008 23:42
		Re: regress question By: Kenneth P. Bowman on Sat, 29 November 2008 07:58
		Re: regress question By: Brian Larsen on Thu, 27 November 2008 07:37
		Re: regress question By: Wout De Nolf on Thu, 27 November 2008 02:47

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