Dear SPM experts,
last year, I have computed DCM for MEG and I have done two types of family inference Bayesian model selection: first, based on connectivity types, second: based on the number of regions.
now I am repeating the same analysis using different versions of SPM and surprisingly I found totally different results with each version!
e.g. with SPM 4010, I found similar result as last year for the family inference based on the connectivity types but totally different result for the second family inference(based on the number of regions).
with SPM4010 but only updating the spm_BMS_gibbs.m (attached to the email), I found similar result for the second family inference but totally different first family inference!!
with SPM4290, I found similar result as SPM4010.
with SPM4667, the result is similar to SPM4010 and updated spm_BMS_gibbs.m
I am very confused and don't know which result is really true?? does anyone knows how I can find this out?
As far as I have learned from the spm emails, this problem is due to a bug in spm_BMS_gibbs.m but the question is when the result is due to a bug and when not.
I am going to do BMS for a new dataset but I am very unsure about the BMS result as it turns out to be unstable.
Thank you very much for your time.
I am looking forward to hear from you.
Best wishes,
Fahimeh
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PhD student
Max Planck Institute for Human Cognitive and Brain Sciences
Stephanstraße 1A
04103 Leipzig
Germany
Tel: +49 341 9940 - 2570
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