[DOC] Add folder description

[lionelkusch]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.28%. Comparing base (d84ea41) to head (d3543bc).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #489   +/-   ##
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  Coverage   99.28%   99.28%           
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  Files          23       23           
  Lines        1253     1253           
=======================================
  Hits         1244     1244           
  Misses          9        9           

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[jpaillard]

I think the description of folder organisation is not so clear.
For most files, the content is quite explicit based on the name and position in the hierarchy.
However, for some folders, the description is not detailed enough. It would be clarified by answering, for example (not exhaustive list): What goes in statistical tools? What is the difference between statistical_tools and _utils? Why is _utils private? Why is multiple_testing not in /src?

[bthirion]

Thx for opening. A few details can be fixed.
How do we ensure that this remains accurate across time ?

[lionelkusch]

How do we ensure that this remains accurate across time ?

I tried to select the file, which will be staying for a long time and won't change name.

[lionelkusch]

I think the description of folder organisation is not so clear. For most files, the content is quite explicit based on the name and position in the hierarchy. However, for some folders, the description is not detailed enough. It would be clarified by answering, for example (not exhaustive list): What goes in statistical tools? What is the difference between statistical_tools and _utils? Why is _utils private? Why is multiple_testing not in /src?

I propose to have the discussion in #86 for the moment for having track of the history of the previous conversation.
This PR is only to present the actual statement of the organization.

[jpaillard]

Could you just add a few lines explaining the rationale behind the decision of placing some modules in statistical_tools in #366?
Just so that we know why things are this way and have some documented precedent that can inform future developments.

[lionelkusch]

Mainly in src/hidimstat, there should be only Conditional feature importance methods.