Re: PSPP multiple linear regression with Y intercept equal zero

[Ether]

Thanks for replying John.

Actually, what I want is the /ORIGIN command (force model to go through origin; i.e. no const term).

I can't fake it by adding a dummy variable with all cases set to zero for three reasons:

1) PSPP does not support weighted multiple linear regression, so adding a single dummy variable to a dataset which already contains hundreds of data points would not force the model's Y intercept to be zero

2) Without weighting, it would be necessary to add hundreds (if not thousands) of dummy data points to force the model's Y intercept to be zero.   This would be unwieldy.

3) Adding hundreds (or thousands) of dummy data points would skew other statistical measures I am interested in.

The following free statistics programs all support zero Y-intercept (no const term) multiple linear regression models:

gretl

R

Octave

Tanagra

ASP

MicrOsiris

LibreOffice Calc

So why don't I just use one of them instead?  Well, I have and I do.  But I have several applications where I want to use PSPP; for example when working with students with prior exposure to SPSS.

---

From: John Darrington <address@hidden>
To: Ether <address@hidden>
Cc: "address@hidden" <address@hidden>
Sent: Thursday, September 1, 2016 7:57 PM
Subject: Re: PSPP multiple linear regression with Y intercept equal zero

Ether,

I'm not an expert on linear regression, but I think you are looking for the /NOORIGIN
subcommand which unfortunately at the moment PSPP doesn't have.

If this is important to you, file a "wishlist" bug and we'll ses what we can do.

In the mean time, you can "fake it" by adding a dummy variable with all cases set
to zero.

J'

On Thu, Sep 01, 2016 at 09:33:32PM +0000, Ether wrote:
   
    Only 2 posts to the PSPP mailing list in the past 7 days.
    Is there a more active PSPP mailing list (or better yet, forum) somewhere?

   
   
--
Avoid eavesdropping.  Send strong encryted email.
PGP Public key ID: 1024D/2DE827B3
fingerprint = 8797 A26D 0854 2EAB 0285  A290 8A67 719C 2DE8 27B3
See http://sks-keyservers.net or any PGP keyserver for public key.