Hi yes strictly you should, though most people don't (correct for
multiple comparisons across contrasts). Note that there may be
correlation across C contrasts so correction by a factors of C may he
overconservative. Cheers
--------------------
Stephen M. Smith, Professor of Biomedical Engineering
Associate Director, Oxford University FMRIB Centre
FMRIB, JR Hospital, Headington,
Oxford. OX3 9 DU, UK
+44 (0) 1865 222726 (fax 222717)
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http://www.fmrib.ox.ac.uk/~steve
----------------------
On 20 Feb 2009, at 15:26, Vishwadeep Ahluwalia <[log in to unmask]>
wrote:
> Hi Steve,
> Ive attached the 2nd level design(LEV2.png) for a single subject.
> Please let
> me know if its correct. Is it valid to have so many t-tests. isnt it a
> multiple comparison problem?
> -vish
> <LEV2.png>
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