Hi Scott
There is another important difference! In SPM2 correlations in the
residual are accounted for by an AR(1) model as opposed to SPM99 where
low-pass filtering was used. In SPM2 a global estimate is calculated
based on a mask defined by the effects of interest. The problem is that
by default your motion covariates is of no interest (in this respect),
but yet they are specified as such by default. This will lead to biased
p-values (in my experience they become too small). To avoid this
unfortunately you need to specify the motion covariates as covariates
of no interest in batch mode. Let me know if you need help with that.
best
torben
Torben E. Lund
Danish Research Centre for MR
Copenhagen University Hospital
Kettegaard Allé 30
2650 Hvidovre
Denmark
email: [log in to unmask]
webpage: http://www.drcmr.dk
On 15 Feb 2005, at 22:06, Cyril PERNET wrote:
> Hi Scott
>
> it works as previously ... :-\
>
> enter 6 as the number of additional regressors and the type in spm_load
> It calls up a window in which you can select your txt-file (all 6
> columns are automatically filled)
>
> Last point, the first line have to be removed if you have registered to
> a mean image
>
> Best,
> cyril
>
>
>
>
> Pernet Cyril
> Neuropsychologist, PhD
> INSERM U455 Pavillon Riser
> CHU Purpan 31059 Toulouse
> France
> Tel: +33(0)561779503
> Fax: +33(0)561499524
> [log in to unmask]
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