Made AIC the default maPCA option

[eurunuela]

Closes #843 .

Changes proposed in this pull request:

• Updated all references to the default maPCA option from mdl to aic.
• Made aic the default maPCA option.
• Updated three-echo test to use aic.

[eurunuela]

I think this PR will fix the failing three-echo test in #839.

[codecov]

Codecov Report

Merging #849 (b28a282) into main (eaa0920) will decrease coverage by 0.18%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #849      +/-   ##
==========================================
- Coverage   93.27%   93.09%   -0.19%     
==========================================
  Files          27       27              
  Lines        2217     2217              
==========================================
- Hits         2068     2064       -4     
- Misses        149      153       +4     

Impacted Files	Coverage Δ
tedana/workflows/tedana.py	89.92% <ø> (ø)
tedana/decomposition/pca.py	86.51% <100.00%> (ø)
tedana/decomposition/ica.py	82.75% <0.00%> (-13.80%)	⬇️

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[tsalo]

Thanks for this. One thing I would like to see added to our documentation is a very short explanation of why we use AIC by default. Something like...

We have chosen AIC as the default PCA criterion because it tends to result in fewer components than the Kundu methods, which increases the likelihood that the ICA step will successfully converge, but also, in our experience, retains enough components for meaningful interpretation later on.

I doesn't have to be that, but something to that effect would be nice. I also think this probably deserves a breaking-change label.

[eurunuela]

Thanks for this. One thing I would like to see added to our documentation is a very short explanation of why we use AIC by default. Something like...

We have chosen AIC as the default PCA criterion because it tends to result in fewer components than the Kundu methods, which increases the likelihood that the ICA step will successfully converge, but also, in our experience, retains enough components for meaningful interpretation later on.

Let me know what you think of the changes added in c610667.

I doesn't have to be that, but something to that effect would be nice. I also think this probably deserves a breaking-change label.

Done!

[handwerkerd]

I'll try to look at this more carefully soon, but one thing I've noticed while running tedana is that there's no logging for various pca options. When the default option is used, I'm not sure anywhere in the log will say what the default option is. I think we should add some logging to places like this

[eurunuela]

I'll try to look at this more carefully soon, but one thing I've noticed while running tedana is that there's no logging for various pca options. When the default option is used, I'm not sure anywhere in the log will say what the default option is. I think we should add some logging to places like this

The logging happens here. The only thing that could be missing in my opinion is the maPCA criteria.

[handwerkerd]

I expanded one comment a bit.
I can't figure out how to suggest a change in an area where you didn't make any edits, but I'd replace
https://github.com/eurunuela/tedana/blob/c61066788779da683d6246dc905b326a74d0bd93/tedana/decomposition/pca.py#L228
with
LGR.info(f"Computing PCA of optimally combined multi-echo data with selection criteria: {algorithm}")

That will have slightly ugly parsing if someone enters a number for algorithm, but, if someone is entering a number, they'll hopefully understand what they're doing.

Otherwise, this all looks good to me.

[eurunuela]

Thank you for your feedback @handwerkerd, b28a282 should address your comments.

[handwerkerd]

LGTM

[jbteves]

LGTM, thanks @eurunuela !