Dear Susie,
We had a bug like this in the lab. So maybe
its the same cause.
FWE, unlike FDR or uncorr, needs an estimate of the
smoothness of the residuals, expressed in FWHM (full
width at half maximum). If you press volume
you should see what SPM estimates it to be. Sensible
estimates are eg. FWHM = 3.0, 3.5, 3.1.
Have a look to see what you have. If its an
unusual number eg. FWHM = 0.0001 or 10000 then
SPM has estimated the smoothness wrong.
Let me know what you have.
Best,
Will.
Susie Henley wrote:
> Dear all,
>
> I am doing a simple t-test between two groups. When I analyse the
> results and look at a simple contrast (group 1 > group 2) I can view
> spms uncorrected or corrected using FDR but after entering 0.05 in the
> FWE box I get the following error message:
>
>
> Warning: Returning NaN for out of range arguments
> > In spm_Pcdf at 88
> In spm_P_RF at 106
> In spm_uc_RF at 37
> In spm_uc at 39
> In spm_getSPM at 545
> In spm_results_ui at 264
> Warning: Returning NaN for out of range arguments
> > In spm_Pcdf at 88
> In spm_P_RF at 106
> In spm_uc_RF at 38
> In spm_uc at 39
> In spm_getSPM at 545
> In spm_results_ui at 264
> ??? Error using ==> betainc
> X must be in the interval [0,1].
>
> Error in ==> spm_Tcdf at 106
> F(Q) = xQxPos
> -(xQxPos*2-1).*0.5.*betainc(v(Qv)./(v(Qv)+x(Qx).^2),v(Qv)/2,1/2);
>
> Error in ==> spm_P_RF>spm_ECdensity at 157
> EC(1,:) = 1 - spm_Tcdf(t,v);
>
> Error in ==> spm_P_RF at 59
> EC = spm_ECdensity(STAT,Z,df);
>
> Error in ==> spm_uc_RF at 47
> p = spm_P_RF(1,0,u,df,STAT,R,n);
>
> Error in ==> spm_uc at 39
> u = spm_uc_RF(a,df,STAT,R,n);
>
> Error in ==> spm_getSPM at 545
> u = spm_uc(u,df,STAT,R,n,S);
>
> Error in ==> spm_results_ui at 264
> [SPM,xSPM] = spm_getSPM;
>
> ??? Error while evaluating uicontrol Callback.
>
> This is after installing the latest updates.
>
> Could someone let me know if they think this is my error or a bug? Is
> there something I am doing wrong that I need to change?
>
> Many thanks,
>
> Susie
>
>
>
--
William D. Penny
Wellcome Department of Imaging Neuroscience
University College London
12 Queen Square
London WC1N 3BG
Tel: 020 7833 7475
FAX: 020 7813 1420
Email: [log in to unmask]
URL: http://www.fil.ion.ucl.ac.uk/~wpenny/
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