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Re: Oneway Anova from a covariance/cross-product matrix?
From: |
John Darrington |
Subject: |
Re: Oneway Anova from a covariance/cross-product matrix? |
Date: |
Thu, 8 Jul 2010 15:19:14 +0000 |
User-agent: |
Mutt/1.5.18 (2008-05-17) |
Thanks, I see that now.
However I think this is going to become an unmitigated nuisance.
We can't always be sure that the dependent variable will be the last
row/column and I see that there is code in the fill_covariance function
in regression.q which rearranges the matrix to satisfy this condition.
I suggest that instead, we change reg_sweep so that it accepts an integer
which is the index of the row/column of the dependent variable. This
would be simple to implement using gsl_matrix_swap_rows/gsl_matrix_swap_columns.
J'
On Wed, Jul 07, 2010 at 11:25:32AM -0400, Jason Stover wrote:
On Tue, Jul 06, 2010 at 07:09:05PM +0000, John Darrington wrote:
> So what exactly do we pass to reg_sweep ?
>
> Passing M doesn't seem to help. If we need to use g or x then that
> requires access to the raw data. I understood that anova could be
calculated
> from M alone.
Almost: reg_sweep expects the final column and row to contain the values
related to
the dependent variable. So it should work with
g1 x
g1 1.5 3.0
x 3.0 16.0
Also, that matrix doesn't contain information related to the
intercept, or "grand mean," meaning you would need to either include
such a column in your covariance matrix, or call
post_sweep_computations.
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- Oneway Anova from a covariance/cross-product matrix?, John Darrington, 2010/07/05
- Re: Oneway Anova from a covariance/cross-product matrix?, Jason Stover, 2010/07/06
- Re: Oneway Anova from a covariance/cross-product matrix?, John Darrington, 2010/07/06
- Re: Oneway Anova from a covariance/cross-product matrix?, Jason Stover, 2010/07/07
- Re: Oneway Anova from a covariance/cross-product matrix?,
John Darrington <=
- Re: Oneway Anova from a covariance/cross-product matrix?, Charles Stangor, 2010/07/09
- Re: Oneway Anova from a covariance/cross-product matrix?, Jason Stover, 2010/07/12
- Re: Oneway Anova from a covariance/cross-product matrix?, Jason Stover, 2010/07/20
- Re: Oneway Anova from a covariance/cross-product matrix?, John Darrington, 2010/07/24