Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-02-27 Thread Ed Gronenschild

Hi Doug,

Can I do this by just permuting the contrast matrix and the  
corresponding columns

in the fsgd file?

Ed

On 26 Feb 2013, at 17:43, freesurfer-requ...@nmr.mgh.harvard.edu wrote:





Hi Ed, I think it is just the way you have the matrix set up. You'll
need to alter the matrix in some way.
doug


Message: 7
Date: Tue, 26 Feb 2013 10:08:07 +0100
From: Ed Gronenschild ed.gronensch...@maastrichtuniversity.nl
Subject: Re: [Freesurfer] Problem with glmfit: matrix is
ill-conditioned
To: freesurfer@nmr.mgh.harvard.edu freesurfer@nmr.mgh.harvard.edu
Message-ID:
2031202f-e366-48cb-82a9-3142378ad...@maastrichtuniversity.nl
Content-Type: text/plain; charset=us-ascii

Hi Doug,

The condition numbers were:
- 1e+08 for problematic fsgd file
- 371.233 for previous fsgd file

I tried also v5.1, however with no succes. The matirx was still
ill-conditioned with condition number 2.80809e+07.

Cheers,
Ed

On 1 Feb 2013, at 9:53, freesurfer-requ...@nmr.mgh.harvard.edu wrote:


Message: 12
Date: Thu, 31 Jan 2013 14:08:11 -0500
From: Douglas N Greve gr...@nmr.mgh.harvard.edu
Subject: Re: [Freesurfer] Problem with glmfit: matrix is
ill-conditioned
To: freesurfer@nmr.mgh.harvard.edu
Message-ID: 510ac11b.4090...@nmr.mgh.harvard.edu
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


Hi Ed, that sounds strange. What were the condition numbers for the
two
analyses? This should be printed out into the terminal. It is also
possible that it is a scaling issue. This should not be an issue in
5.1,
but it is possible that it could have an effect if two columns are
very
similar.
doug


On 01/30/2013 05:10 AM, Ed Gronenschild wrote:


Hi Doug,

It is indeed correct that columns 1 and 17 are highly correlated.
However,
for another version of the fsgd file, where the corresponding
class and
covariate values where identical but with other covariates (so
leading to
the same columns  1 and 17, other columns are different), all went
well.
So probably some other columns are highly correlated as well.
Anyway, what can we do about it? Just leave the offending covariate
(s)
out?

Cheers,
Ed




Message: 1
Date: Thu, 24 Jan 2013 12:51:23 -0500
From: Douglas N Greve gr...@nmr.mgh.harvard.edu
mailto:gr...@nmr.mgh.harvard.edu
Subject: Re: [Freesurfer] Problem with glmfit: matrix is
  ill-conditioned
To: freesurfer@nmr.mgh.harvard.edu
mailto:freesurfer@nmr.mgh.harvard.edu
Message-ID: 5101749b.4060...@nmr.mgh.harvard.edu
mailto:5101749b.4060...@nmr.mgh.harvard.edu
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi Ed, the problem is that your covariates are highly correlated.
Eg,
column 1 is nearly identical to column 17.
doug


On 01/24/2013 06:36 AM, Ed Gronenschild wrote:

Hi,

Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following
error message:

ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08
Possible problem with experimental design:
Check for duplicate entries and/or lack of range of
continuous variables within a class.
If you seek help with this problem, make sure to send:
  1. Your command line:
mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh
--fsgd
../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/
fsgd_sib_con_cann_aangepast3.fsgd
dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf
fsaverage lh --C
../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/
group_thickness_gender_scan_age_educ_hand_cann.mtx

  2. The FSGD file (if using one)
  3. And the design matrix above

Please find attached the requested files.

I noticed that rows 68 and 147 of the matrix Xg.dat are identical,
and most probably caused the error.
In the fsgd file I see that the correspondig cases indeed have
identical values, although they are referring to different data.
How to proceed?

Cheers,
Ed





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--
Douglas N. Greve, Ph.D.
MGH-NMR Center
gr...@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422

Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html
Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/
greve/


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Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-02-27 Thread Douglas N Greve

Hi Ed, permuting the matrix will not help. The problem is that some 
weighted combination of columns is equal to some other column. It means 
thatsome of your covariates are highly correlated. Sometimesthis is 
obvious (eg, two columns are the same), other times it is very subtle. 
You will need to look carefully at your covariates to see if some are 
correlated. This might be a mathematical examination, but it could also 
be qualitative (eg, age and weight in children will correlate). Sorry I 
can't give you more guidance.
doug

On 02/27/2013 11:24 AM, Ed Gronenschild wrote:
 Hi Doug,

 Can I do this by just permuting the contrast matrix and the 
 corresponding columns
 in the fsgd file?

 Ed

 On 26 Feb 2013, at 17:43, freesurfer-requ...@nmr.mgh.harvard.edu 
 mailto:freesurfer-requ...@nmr.mgh.harvard.edu wrote:

 Hi Ed, I think it is just the way you have the matrix set up. You'll
 need to alter the matrix in some way.
 doug

 Message: 7

 Date: Tue, 26 Feb 2013 10:08:07 +0100

 From: Ed Gronenschild ed.gronensch...@maastrichtuniversity.nl 
 mailto:ed.gronensch...@maastrichtuniversity.nl

 Subject: Re: [Freesurfer] Problem with glmfit: matrix is

 ill-conditioned

 To: freesurfer@nmr.mgh.harvard.edu 
 mailto:freesurfer@nmr.mgh.harvard.edu 
 freesurfer@nmr.mgh.harvard.edu mailto:freesurfer@nmr.mgh.harvard.edu

 Message-ID:

 2031202f-e366-48cb-82a9-3142378ad...@maastrichtuniversity.nl 
 mailto:2031202f-e366-48cb-82a9-3142378ad...@maastrichtuniversity.nl

 Content-Type: text/plain; charset=us-ascii


 Hi Doug,


 The condition numbers were:

 - 1e+08 for problematic fsgd file

 - 371.233 for previous fsgd file


 I tried also v5.1, however with no succes. The matirx was still

 ill-conditioned with condition number 2.80809e+07.


 Cheers,

 Ed


 On 1 Feb 2013, at 9:53, freesurfer-requ...@nmr.mgh.harvard.edu 
 mailto:freesurfer-requ...@nmr.mgh.harvard.edu wrote:


 Message: 12

 Date: Thu, 31 Jan 2013 14:08:11 -0500

 From: Douglas N Greve gr...@nmr.mgh.harvard.edu 
 mailto:gr...@nmr.mgh.harvard.edu

 Subject: Re: [Freesurfer] Problem with glmfit: matrix is

 ill-conditioned

 To: freesurfer@nmr.mgh.harvard.edu 
 mailto:freesurfer@nmr.mgh.harvard.edu

 Message-ID: 510ac11b.4090...@nmr.mgh.harvard.edu 
 mailto:510ac11b.4090...@nmr.mgh.harvard.edu

 Content-Type: text/plain; charset=ISO-8859-1; format=flowed



 Hi Ed, that sounds strange. What were the condition numbers for the

 two

 analyses? This should be printed out into the terminal. It is also

 possible that it is a scaling issue. This should not be an issue in

 5.1,

 but it is possible that it could have an effect if two columns are

 very

 similar.

 doug



 On 01/30/2013 05:10 AM, Ed Gronenschild wrote:


 Hi Doug,


 It is indeed correct that columns 1 and 17 are highly correlated.

 However,

 for another version of the fsgd file, where the corresponding

 class and

 covariate values where identical but with other covariates (so

 leading to

 the same columns1 and 17, other columns are different), all went

 well.

 So probably some other columns are highly correlated as well.

 Anyway, what can we do about it? Just leave the offending covariate

 (s)

 out?


 Cheers,

 Ed




 Message: 1

 Date: Thu, 24 Jan 2013 12:51:23 -0500

 From: Douglas N Greve gr...@nmr.mgh.harvard.edu 
 mailto:gr...@nmr.mgh.harvard.edu

 mailto:gr...@nmr.mgh.harvard.edu

 Subject: Re: [Freesurfer] Problem with glmfit: matrix is

 ill-conditioned

 To: freesurfer@nmr.mgh.harvard.edu 
 mailto:freesurfer@nmr.mgh.harvard.edu

 mailto:freesurfer@nmr.mgh.harvard.edu

 Message-ID: 5101749b.4060...@nmr.mgh.harvard.edu 
 mailto:5101749b.4060...@nmr.mgh.harvard.edu

 mailto:5101749b.4060...@nmr.mgh.harvard.edu

 Content-Type: text/plain; charset=ISO-8859-1; format=flowed


 Hi Ed, the problem is that your covariates are highly correlated.

 Eg,

 column 1 is nearly identical to column 17.

 doug



 On 01/24/2013 06:36 AM, Ed Gronenschild wrote:

 Hi,


 Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following

 error message:


 ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08

 Possible problem with experimental design:

 Check for duplicate entries and/or lack of range of

 continuous variables within a class.

 If you seek help with this problem, make sure to send:

 1. Your command line:

 mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh

 --fsgd

 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/

 fsgd_sib_con_cann_aangepast3.fsgd

 dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf

 fsaverage lh --C

 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/

 group_thickness_gender_scan_age_educ_hand_cann.mtx


 2. The FSGD file (if using one)

 3. And the design matrix above


 Please find attached the requested files.


 I noticed that rows 68 and 147 of the matrix Xg.dat are identical,

 and most probably caused the error.

 In the fsgd file I see that the correspondig cases indeed have

 identical values, although

Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-02-26 Thread Ed Gronenschild

Hi Doug,

The condition numbers were:
- 1e+08 for problematic fsgd file
- 371.233 for previous fsgd file

I tried also v5.1, however with no succes. The matirx was still
ill-conditioned with condition number 2.80809e+07.

Cheers,
Ed

On 1 Feb 2013, at 9:53, freesurfer-requ...@nmr.mgh.harvard.edu wrote:


Message: 12
Date: Thu, 31 Jan 2013 14:08:11 -0500
From: Douglas N Greve gr...@nmr.mgh.harvard.edu
Subject: Re: [Freesurfer] Problem with glmfit: matrix is
ill-conditioned
To: freesurfer@nmr.mgh.harvard.edu
Message-ID: 510ac11b.4090...@nmr.mgh.harvard.edu
Content-Type: text/plain; charset=ISO-8859-1; format=flowed


Hi Ed, that sounds strange. What were the condition numbers for the  
two

analyses? This should be printed out into the terminal. It is also
possible that it is a scaling issue. This should not be an issue in  
5.1,
but it is possible that it could have an effect if two columns are  
very

similar.
doug


On 01/30/2013 05:10 AM, Ed Gronenschild wrote:


Hi Doug,

It is indeed correct that columns 1 and 17 are highly correlated.  
However,
for another version of the fsgd file, where the corresponding  
class and
covariate values where identical but with other covariates (so  
leading to
the same columns  1 and 17, other columns are different), all went  
well.

So probably some other columns are highly correlated as well.
Anyway, what can we do about it? Just leave the offending covariate 
(s)

out?

Cheers,
Ed




Message: 1
Date: Thu, 24 Jan 2013 12:51:23 -0500
From: Douglas N Greve gr...@nmr.mgh.harvard.edu
mailto:gr...@nmr.mgh.harvard.edu
Subject: Re: [Freesurfer] Problem with glmfit: matrix is
  ill-conditioned
To: freesurfer@nmr.mgh.harvard.edu
mailto:freesurfer@nmr.mgh.harvard.edu
Message-ID: 5101749b.4060...@nmr.mgh.harvard.edu
mailto:5101749b.4060...@nmr.mgh.harvard.edu
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi Ed, the problem is that your covariates are highly correlated.  
Eg,

column 1 is nearly identical to column 17.
doug


On 01/24/2013 06:36 AM, Ed Gronenschild wrote:

Hi,

Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following
error message:

ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08
Possible problem with experimental design:
Check for duplicate entries and/or lack of range of
continuous variables within a class.
If you seek help with this problem, make sure to send:
  1. Your command line:
mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh  
--fsgd
../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/ 
fsgd_sib_con_cann_aangepast3.fsgd

dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf
fsaverage lh --C
../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/ 
group_thickness_gender_scan_age_educ_hand_cann.mtx


  2. The FSGD file (if using one)
  3. And the design matrix above

Please find attached the requested files.

I noticed that rows 68 and 147 of the matrix Xg.dat are identical,
and most probably caused the error.
In the fsgd file I see that the correspondig cases indeed have
identical values, although they are referring to different data.
How to proceed?

Cheers,
Ed





___
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer


--
Douglas N. Greve, Ph.D.
MGH-NMR Center
gr...@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422

Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html
Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/ 
greve/


___
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https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer


The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.


Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-02-26 Thread Douglas N Greve
Hi Ed, I think it is just the way you have the matrix set up. You'll 
need to alter the matrix in some way.
doug

On 02/26/2013 04:08 AM, Ed Gronenschild wrote:
 Hi Doug,

 The condition numbers were:
 - 1e+08 for problematic fsgd file
 - 371.233 for previous fsgd file

 I tried also v5.1, however with no succes. The matirx was still
 ill-conditioned with condition number 2.80809e+07.

 Cheers,
 Ed

 On 1 Feb 2013, at 9:53, freesurfer-requ...@nmr.mgh.harvard.edu 
 mailto:freesurfer-requ...@nmr.mgh.harvard.edu wrote:

 Message: 12

 Date: Thu, 31 Jan 2013 14:08:11 -0500

 From: Douglas N Greve gr...@nmr.mgh.harvard.edu 
 mailto:gr...@nmr.mgh.harvard.edu

 Subject: Re: [Freesurfer] Problem with glmfit: matrix is

 ill-conditioned

 To: freesurfer@nmr.mgh.harvard.edu 
 mailto:freesurfer@nmr.mgh.harvard.edu

 Message-ID: 510ac11b.4090...@nmr.mgh.harvard.edu 
 mailto:510ac11b.4090...@nmr.mgh.harvard.edu

 Content-Type: text/plain; charset=ISO-8859-1; format=flowed



 Hi Ed, that sounds strange. What were the condition numbers for the two

 analyses? This should be printed out into the terminal. It is also

 possible that it is a scaling issue. This should not be an issue in 5.1,

 but it is possible that it could have an effect if two columns are very

 similar.

 doug



 On 01/30/2013 05:10 AM, Ed Gronenschild wrote:


 Hi Doug,


 It is indeed correct that columns 1 and 17 are highly correlated. 
 However,

 for another version of the fsgd file, where the corresponding class and

 covariate values where identical but with other covariates (so 
 leading to

 the same columns1 and 17, other columns are different), all went well.

 So probably some other columns are highly correlated as well.

 Anyway, what can we do about it? Just leave the offending covariate(s)

 out?


 Cheers,

 Ed




 Message: 1

 Date: Thu, 24 Jan 2013 12:51:23 -0500

 From: Douglas N Greve gr...@nmr.mgh.harvard.edu 
 mailto:gr...@nmr.mgh.harvard.edu

 mailto:gr...@nmr.mgh.harvard.edu

 Subject: Re: [Freesurfer] Problem with glmfit: matrix is

 ill-conditioned

 To: freesurfer@nmr.mgh.harvard.edu 
 mailto:freesurfer@nmr.mgh.harvard.edu

 mailto:freesurfer@nmr.mgh.harvard.edu

 Message-ID: 5101749b.4060...@nmr.mgh.harvard.edu 
 mailto:5101749b.4060...@nmr.mgh.harvard.edu

 mailto:5101749b.4060...@nmr.mgh.harvard.edu

 Content-Type: text/plain; charset=ISO-8859-1; format=flowed


 Hi Ed, the problem is that your covariates are highly correlated. Eg,

 column 1 is nearly identical to column 17.

 doug



 On 01/24/2013 06:36 AM, Ed Gronenschild wrote:

 Hi,


 Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following

 error message:


 ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08

 Possible problem with experimental design:

 Check for duplicate entries and/or lack of range of

 continuous variables within a class.

 If you seek help with this problem, make sure to send:

 1. Your command line:

 mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh --fsgd

 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/fsgd_sib_con_cann_aangepast3.fsgd

 dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf

 fsaverage lh --C

 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/group_thickness_gender_scan_age_educ_hand_cann.mtx


 2. The FSGD file (if using one)

 3. And the design matrix above


 Please find attached the requested files.


 I noticed that rows 68 and 147 of the matrix Xg.dat are identical,

 and most probably caused the error.

 In the fsgd file I see that the correspondig cases indeed have

 identical values, although they are referring to different data.

 How to proceed?


 Cheers,

 Ed




 ___

 Freesurfer mailing list

 Freesurfer@nmr.mgh.harvard.edu mailto:Freesurfer@nmr.mgh.harvard.edu

 https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer


 --

 Douglas N. Greve, Ph.D.

 MGH-NMR Center

 gr...@nmr.mgh.harvard.edu mailto:gr...@nmr.mgh.harvard.edu

 Phone Number: 617-724-2358

 Fax: 617-726-7422


 Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting

 FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html 
 http://www.nmr.mgh.harvard.edu/facility/filedrop/index.html

 Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/greve/




 ___
 Freesurfer mailing list
 Freesurfer@nmr.mgh.harvard.edu
 https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer

-- 
Douglas N. Greve, Ph.D.
MGH-NMR Center
gr...@nmr.mgh.harvard.edu
Phone Number: 617-724-2358
Fax: 617-726-7422

Bugs: surfer.nmr.mgh.harvard.edu/fswiki/BugReporting
FileDrop: www.nmr.mgh.harvard.edu/facility/filedrop/index.html
Outgoing: ftp://surfer.nmr.mgh.harvard.edu/transfer/outgoing/flat/greve/

___
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The information in this e-mail is intended only

Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-01-30 Thread Ed Gronenschild

Hi Doug,

It is indeed correct that columns 1 and 17 are highly correlated. However,
for another version of the fsgd file, where the corresponding class and
covariate values where identical but with other covariates (so leading to
the same columns  1 and 17, other columns are different), all went well.
So probably some other columns are highly correlated as well.
Anyway, what can we do about it? Just leave the offending covariate(s) out?

Cheers,
Ed



 Message: 1
 Date: Thu, 24 Jan 2013 12:51:23 -0500
 From: Douglas N Greve gr...@nmr.mgh.harvard.edu
 Subject: Re: [Freesurfer] Problem with glmfit: matrix is
 ill-conditioned
 To: freesurfer@nmr.mgh.harvard.edu
 Message-ID: 5101749b.4060...@nmr.mgh.harvard.edu
 Content-Type: text/plain; charset=ISO-8859-1; format=flowed
 
 Hi Ed, the problem is that your covariates are highly correlated. Eg,
 column 1 is nearly identical to column 17.
 doug
 
 
 On 01/24/2013 06:36 AM, Ed Gronenschild wrote:
 Hi,
 
 Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following
 error message:
 
 ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08
 Possible problem with experimental design:
 Check for duplicate entries and/or lack of range of
 continuous variables within a class.
 If you seek help with this problem, make sure to send:
   1. Your command line:
 mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh --fsgd
 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/fsgd_sib_con_cann_aangepast3.fsgd
 dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf
 fsaverage lh --C
 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/group_thickness_gender_scan_age_educ_hand_cann.mtx
 
   2. The FSGD file (if using one)
   3. And the design matrix above
 
 Please find attached the requested files.
 
 I noticed that rows 68 and 147 of the matrix Xg.dat are identical,
 and most probably caused the error.
 In the fsgd file I see that the correspondig cases indeed have
 identical values, although they are referring to different data.
 How to proceed?
 
 Cheers,
 Ed

 
___
Freesurfer mailing list
Freesurfer@nmr.mgh.harvard.edu
https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer


The information in this e-mail is intended only for the person to whom it is
addressed. If you believe this e-mail was sent to you in error and the e-mail
contains patient information, please contact the Partners Compliance HelpLine at
http://www.partners.org/complianceline . If the e-mail was sent to you in error
but does not contain patient information, please contact the sender and properly
dispose of the e-mail.


Re: [Freesurfer] Problem with glmfit: matrix is ill-conditioned

2013-01-24 Thread Douglas N Greve
Hi Ed, the problem is that your covariates are highly correlated. Eg, 
column 1 is nearly identical to column 17.
doug


On 01/24/2013 06:36 AM, Ed Gronenschild wrote:
 Hi,

 Running mri_glmfit ( v5.0.0, Mac OSX10.6) I got he following
 error message:

 ERROR: matrix is ill-conditioned or badly scaled, condno = 1e+08
 Possible problem with experimental design:
 Check for duplicate entries and/or lack of range of
 continuous variables within a class.
 If you seek help with this problem, make sure to send:
   1. Your command line:
 mri_glmfit --y lh.sib_con_cann_aangepast3.thickness.sm0.mgh --fsgd 
 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/fsgd_sib_con_cann_aangepast3.fsgd
  
 dods --glmdir lh.sib_con_cann_aangepast3.dods.sm0.glmdir --surf 
 fsaverage lh --C 
 ../../STATS/FSGD/age_gender_scan_educ_hand_cannabis/group_thickness_gender_scan_age_educ_hand_cann.mtx
  

   2. The FSGD file (if using one)
   3. And the design matrix above

 Please find attached the requested files.

 I noticed that rows 68 and 147 of the matrix Xg.dat are identical,
 and most probably caused the error.
 In the fsgd file I see that the correspondig cases indeed have
 identical values, although they are referring to different data.
 How to proceed?

 Cheers,
 Ed

 =








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