scikit-learn / scikit-learn/scikit-learn

[RFC] Deprecate n_samples_seen_ in MaxAbsScaler and MinMaxScaler

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#11,300 2 comments 0 reactions 0 assignees View on GitHub

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module:preprocessing Needs Decision
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Python
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Description

MinMaxScaler and MaxAbsScaler have an attribute n_samples_seen which is not used to compute the statistics. For instance this is useful to have it in StandardScaler but does not bring anything in those 2 scalers.

In #11011, @jnothman proposed to deprecate this parameter which I am also in favor of.

@amueller @ogrisel Any opinion and historical reasons why this attribute is there (because the class have a partial_fit method?

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  3. Fork the repository and make your change on a branch.
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Research direction

Start by reading the MinMaxScaler and MaxAbsScaler implementations and the discussion in #11011. Check how n_samples_seen_ is exposed and whether partial_fit depends on it, then establish the deprecation behavior and affected tests before making the change. Done means the unused attribute is deprecated consistently without altering scaler statistics.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
machine-learning
Issue type
Refactor
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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