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Hi Levi,

You can skip Text2Vest and open a simple text editor and type your design
matrix and contrast file (just make sure to use Unix line endings when
saving, which is usually the default in Linux anyway). It's just a text
file, really. If you still can't get it right, send the 100x1 file you have
(e.g. a spreadsheet) and someone in the list can help you to convert it
quickly.

All the best,

Anderson


On 26 October 2015 at 15:19, LEVI SOLOMYAK <[log in to unmask]>
wrote:

> 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
>>>>>
>>>>
>>>>
>>>
>>
>