Re: [OctDev] regress and rcoplot (partially written, please help)

[Paul K. <pki...@us...>]

On Jan 1, 2006, at 4:20 AM, William Poetra Yoga Hadisoeseno wrote:

> OK, today I finally finished the function (I think). I used Paul's
> notes at the end of wsolve.m. Take a look at the attachment ;)

You are not using the economy QR decomposition.  This can lead to
very large matrices for over determined systems.

Also, you should generally avoid computing the full inverse as
part of solving a system.  It is more expensive and I believe
less stable than working directly off the QR decomposition that
you have already computed.

Any reason you did not use my wsolve code as it stands?

Similarly, do you have a reason for not using the code I sent
for computing confidence intervals, which also avoids direct
computation of the inverse?

If there is some reason to prefer your code I would like
to know what it is.

- Paul