It's just that the first 3 EVs have zero mean, and the sole purpose of
EV4 is to model the global mean, so you could alternatively drop EV4
and demean the data.
Cheers.
On 4 Dec 2007, at 10:05, Agnieszka Burzynska wrote:
> Dear Steve,
> Thank you very much for your reply. But why I should demean my data
> at all
> here? This is not clear to me....
>
> Best wishes,
> Aga
>
>
> On 03.12.2007 10:33 Uhr, "Steve Smith" <[log in to unmask]> wrote:
>
>> Hi,
>>
>> Your EV4 is just modelling the whole-group mean, which is fine.
>> Alternatively, you could just omit EV4 and demean the data instead
>> using the -D flag in randomise.
>>
>> Cheers.
>>
>>
>>
>>
>> On 30 Nov 2007, at 14:56, Agnieszka Burzynska wrote:
>>
>>>
>>> Hi,
>>>
>>> I have a problem with design for randomise analysis of tbss data and
>>> didnt find answers in the archives:
>>>
>>> -I use Glm_gui to set up the design matrix
>>> -First i compared patients vs controls: I had:
>>> (design.con)
>>> /ContrastName1 controls>patients
>>> /ContrastName2 patients>controls
>>> /NumWaves 2
>>> /NumContrasts 2
>>> /PPheights 1.000000e+00 1.000000e+00
>>> /RequiredEffect 1.501 1.501
>>> /Matrix
>>> 1.000000e+00 -1.000000e+00
>>> -1.000000e+00 1.000000e+00
>>>
>>> design.mat
>>> /NumWaves 2
>>> /NumPoints 35
>>> /PPheights 1.000000e+00 1.000000e+00
>>>
>>> /Matrix
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 1.000000e+00 0.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>> 0.000000e+00 1.000000e+00
>>>
>>> -now I want to see the interaction with age --> as far as I know
>>> ANOVA 2x2 design is suitable. I used the information at ...fsl/
>>> feat5/
>>> detail.html#higher to create the below matrix:
>>>
>>> EV1 I assume is patient (-1) and control (1)
>>> EV2 is sex: male (1) and female (-1)
>>> EV3 is the product of EV1 and EV2
>>> But what is EV4 here in case of FA data from tbss?
>>>
>>> I will be very grateful for all suggestions,
>>> (also about which other model to use for such data if ANOVA is not
>>> recommended for this data?)
>>> Best wishes,
>>> Aga
>>>
>>> /ContrastName1 patient/control
>>> /ContrastName2 sex
>>> /ContrastName3 patient/control x sex
>>> /NumWaves 4
>>> /NumContrasts 3
>>> /PPheights 2.060606e+00 2.060606e+00 2.060606e+00
>>> /RequiredEffect 1.574 1.574 1.574
>>>
>>> /Matrix
>>> 1.000000e+00 0.000000e+00 0.000000e+00 0.000000e+00
>>> 0.000000e+00 1.000000e+00 0.000000e+00 0.000000e+00
>>> 0.000000e+00 0.000000e+00 1.000000e+00 0.000000e+00
>>>
>>> /NumWaves 4
>>> /NumPoints 35
>>> /PPheights 2.000000e+00 2.000000e+00 2.000000e+00
>>> 1.000000e+00
>>>
>>> /Matrix
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 1.000000e+00 1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> 1.000000e+00 -1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 1.000000e+00 -1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>> -1.000000e+00 -1.000000e+00 1.000000e+00 1.000000e+00
>>
>>
>> ---------------------------------------------------------------------------
>> 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
>> ---------------------------------------------------------------------------
---------------------------------------------------------------------------
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
---------------------------------------------------------------------------
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