Dear Dr. Penny,
Dear all,
I`m using the flexible factorial design specification in SPM5 to specify a
mixed design with a within-subject factor reward_level (4 levels) and a
between-subject factor group (2 groups).
When I try to estimate the model the following error occurred:
SPM5: spm_spm (v$Rev: 301 $) 17:19:06 - 03/06/2006
========================================================================
Initialising parameters : ...done
...initialised
Plane 69/69 , block 1/1 : ...done
Temporal non-sphericity (over voxels) : ...REML estimation
??? Error using ==> plus
Matrix dimensions must agree.
Error in ==> spm_reml at 87
C = C + Q{i}*h(i);
Error in ==> spm_spm at 860
[V,h] = spm_reml(Cy,xX.X,xVi.Vi);
Error in ==> spm_getSPM at 210
[SPM] = spm_spm(SPM);
Error in ==> spm_results_ui at 260
[SPM,xSPM] = spm_getSPM;
??? Error while evaluating uicontrol Callback.
When specifying a within-subject ANOVA (without the between-subject
factor)the estimatation of the model is working fine.
I`m wondering whether there is something wrong with my design specification
or could this be related to the following note of Dr. Will Penny?
Date: Wed, 21 Dec 2005 12:09:16 +0000
Reply-To: Will Penny <[log in to unmask]>
Subject: Re: spm5 repeated measures ANOVA
Comments: To: Martin Kronbichler <[log in to unmask]>
**A note of caution**. There is currently a bug in SPM5 when specifying
nonsphericity for 2 or 3 way ANOVAs. We are working on a fix.
Design specification in SPM5, matlab 71:
1) 'Flexible Factorial' design
2) Factors: subject (reserved word – no condition vector necessary),
reward_level, group
3) 'Specify Subject or all Scans and Factors': 'Subjects'
4) 'Scans' , 'Specify Files' : 4 con images for each subject(reward level
1,2,3,4)
5) 'Conditions': [1 2 3 4; 1 1 1 1] for all subjects of the first group and
[1 2 3 4; 2 2 2 2] for all subjects of the second group.
6) 'Main effects and interactions':
Main Effect 1 (reward_level): 2
Main Effect 2 (group): 3
Interaction (group*reward_level): 3 2
Main Effect 3 (subject/constant): 1
Any suggestions would be appreciated.
Many thanks
Mira
|