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Hi Anderson,

Thank you so much for your explanation. I think I'm just struggling with
using Text2Vest to generate the number of waves/points that I need.
Specifically, I am trying to correlate Fa values to a single behavioral
measure so need my design matrix to be 100X1, and my contrast matrix to
simply to represent the single EV.

However, I cannot find a format in which Text2Vest will probably create the
contrast file for me. Just a 1 for a single contrast will give me a
division by 0 error and a 1 0 gives me a 1X2 matrix which is not what I
need.

Thank you so much,
Levi

On Sat, Oct 17, 2015 at 4:38 AM, Anderson M. Winkler <[log in to unmask]
> wrote:

> Hi,
>
> Maybe that example was too tiny to be useful. The file contains a matrix.
> Each row of this matrix is a t-contrast.
>
> The /NumWaves is the number of columns in this matrix (which corresponds
> to the number of EVs in the design matrix), and /NumPoints is the number of
> rows (which corresponds to the number of t-contrasts).
>
> If you want a single contrast as [1 -1], that is, comparing the regression
> coefficients for EV1 with EV2, the contrast file would be:
>
> /NumWaves 2
> /NumPoints 1
>
> /Matrix
> 1 -1
>
> All the best,
>
> Anderson
>
>
> On 16 October 2015 at 17:28, LEVI SOLOMYAK <[log in to unmask]>
> wrote:
>
>> Hi Anderson,
>>
>> Thank you so much for your suggestion. When I try and create the contrast
>> file from that matrix (1, -1), it interprets it as NumWaves 2 and NumPoints
>> 1. Is there some simple way so that it defines the contrast the other way?
>>
>> Thank you so much,
>> CN
>>
>> On Fri, Sep 25, 2015 at 2:15 AM, Anderson M. Winkler <
>> [log in to unmask]> wrote:
>>
>>> Hi Corey,
>>>
>>> Can't say without seeing what you are doing, but in any case, with a
>>> single EV, you can create the design.mat by hand. It's a text file that
>>> looks like this:
>>>
>>> /NumWaves 1
>>> /NumPoints 100
>>>
>>> /Matrix
>>> xx
>>> xx
>>> xx
>>> xx
>>> xx
>>> ...
>>>
>>> Where the "xx" are the numerical values you have for the EV. The
>>> design.con follows a similar structure:
>>>
>>> /NumWaves 1
>>> /NumPoints 2
>>>
>>> /Matrix
>>> 1
>>> -1
>>>
>>> When running randomise, include the option -D.
>>>
>>> All the best,
>>>
>>> Anderson
>>>
>>>
>>>
>>> On 24 September 2015 at 16:38, Corey N <[log in to unmask]>
>>> wrote:
>>>
>>>> Dear FSl Experts,
>>>>
>>>> I am hoping to run a one sample t-test using GLM to find correlations
>>>> between FA values and a behavioral measure. Since all of my subjects are in
>>>> a single group, my design matrix is simply the behavioral value. Is that
>>>> correct?
>>>>
>>>> Because I am working with 100 subjects, I used Text2Vest to convert my
>>>> contrast matrix. I tried to do the same for the design matrix (1) since
>>>> theres only 1 ev but get a expr: division by zero.
>>>>
>>>> Am I setting up my GLM correctly? And if so, what is my mistake with
>>>> Text2Vest?
>>>>
>>>> Thank you so much
>>>> CN
>>>>
>>>
>>>
>>
>