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Hi - at second level, with the FE option, you do not need to include one EV per run, as the FE modelling is not trying to model the cross- run variance anyway, it is just pooling across the first-level variances (that's the definition of a FE model). So if you do this (i.e., following the example from the FEAT manual) all should work ok. Cheers. On 13 Oct 2008, at 21:43, Michael W. Cole wrote: > Hello, > > I'm using FEAT to run a 3-level analysis. My study has 10 runs per > subject with 15 subjects. The second level combines runs (using > fixed-effects) and the third level combines subjects (using mixed- > effects). I included a separate EV for each run at the second level > to remove inter-run mean effects (making it repeated-measures). I > tried doing this (one EV per subject) at the 3rd level, using FLAME, > and I get this error: "Singular design. Number of EVs > number of > time points." and the script crashes. It works, however, if I > perform a fixed-effects analysis instead of using FLAME. > > Is there a better way to account for run and subject differences in > these models? Why would this work with fixed-effects but not FLAME? > > Thank you, > Michael > > > -- > Michael W. Cole > Ph.D. candidate, Center for Neuroscience > University of Pittsburgh --------------------------------------------------------------------------- Stephen M. Smith, Professor of Biomedical Engineering Associate Director, Oxford University FMRIB Centre FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK +44 (0) 1865 222726 (fax 222717) [log in to unmask] http://www.fmrib.ox.ac.uk/~steve ---------------------------------------------------------------------------