Fumiko -
This has nothing to do with ANOVAs, but is true for any F-contrast (I
think): i.e, I don't think cluster-level p-values have been implemented for
the F statistic in SPM (yet) - only for T and Z - but perhaps someone will
correct me.
Rik
--------------------------------------------------------
DR RICHARD HENSON
MRC Cognition & Brain Sciences Unit
15 Chaucer Road, Cambridge,
CB2 2EF England
EMAIL: [log in to unmask]
URL: http://www.mrc-cbu.cam.ac.uk/~rik.henson
TEL +44 (0)1223 355 294 x522
FAX +44 (0)1223 359 062
MOB +44 (0)794 1377 345
--------------------------------------------------------
>-----Original Message-----
>From: SPM (Statistical Parametric Mapping)
>[mailto:[log in to unmask]] On Behalf Of Fumiko Hoeft
>Sent: 03 April 2006 16:29
>To: [log in to unmask]
>Subject: [SPM] Q: one way ANOVA (3 groups) main effect of
>group (whole brain correction using height and extent threshold)
>
>
>To Dr.s Henson, Penny and others,
>
>We are trying to look at the main effect for group using
>one-way ANOVA as
>described in Drs Henson and Penny's chapter entitled 'ANOVAs
>and SPM'. We
>would like to use a threshold using the joint-expected probability
>distribution (Polini et al 1997) with height and extent
>thresholds corrected
>at the whole-brain level.
>
>When we do the effects of interest F-contrast =[1 -1/2 -1/2; -1/2
>1 -1/2; -1/2 -1/2 1], and clik on the volume button, the
>cluster level P
>corrected and uncorrected columns are empty, hence cannot
>implement the dual
>threshold approach by Polini et al.
>
>If anyone can give us some suggestions, that would be great.
>
>Thanks very much in advance.
>
>Best,
>
>Fumiko
>
>--
>Fumiko Hoeft, MD, PhD
>Stanford University School of Medicine
>Center for Interdisciplinary Brain Sciences Research
>401 Quarry Rd. Stanford CA USA 94305-5795
>-----
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