MLJ 0.17, ScientificTypes 3.0 update

[ablaom]

Time to update all the tutorials once more. Breaking changes listed here.

Probably the main changes are:

• EnsmbleModel(atom=...) is now EnsembleModel(model=...) (breaking)
• @pipeline is deprecated in favour of macro free pipelines (using |> syntax) and the use of the new wrapper TransformedTargetModel(model=..., target=..., ) for target transformations.
• added If the last predicate in unpack(...) is of the form _ -> true, then it can be dropped (Change unpack to avoid colname -> true mystery MLJBase.jl#621)
• added the entire section on "arrow syntax" can be dropped, as this syntax has been usurped by pipelines

Todo:

• Data Basics (D0-)
• Getting Started (A-)
  • A-learning-networks (removed the arrow section)
  • A-model-choice (unpack)
  • A-model-tuning (ensemble)
  • A-ensemble (ensemble)
  • A-enseemble2 (ensemble)
• Intro to Stats (ISL-)
  • ISL8 (unpack)
• End-to-end Examples (EX-)
  • airfoil (unpack)
  • houseking (unpack)

cc @OkonSamuel

[ablaom]

@OkonSamuel Note that I have added two points to the first list.

[tlienart]

Had a quick first go at this but am failing to precompile 0.17 on 1.7.1 which is not ideal. will do a bit of digging but in the meantime if someone has an idea ..

EDIT: fixed

[tlienart]

To better understand the pipeline stuff, could I get guidance on how to update this?

pipe = @pipeline(
    X -> coerce(X, :age=>Continuous),
    OneHotEncoder(),
    KNNRegressor(K=3),
    target = UnivariateStandardizer());

[OkonSamuel]

pipe = @pipeline(
X -> coerce(X, :age=>Continuous),
OneHotEncoder(),
KNNRegressor(K=3),
target = UnivariateStandardizer())

This would just be

pipe = (X -> coerce(X, :age=>Continuous)) |> 
    OneHotEncoder() |>
    KNNRegressor(K=3)

model = TransformedTargetModel(
    pipe,
    target = UnivariateStandardizer
)

[ablaom]

I'd probably invert the composition here - first wrap KNN in a target transformer and then insert into the pipeline.

See https://github.com/ablaom/MLJTutorial.jl/tree/dev/notebooks/03_pipelines which is already revised for examples.

[tlienart]

Ideally if you guys could suggest copy-pastable replacements in the PR for the places where this appears:

1. A-composing-models
2. EX-GLM
3. EX-horse
4. EX-wine
5. ISL-lab-5
6. ISL-lab-6b
7. ISL-lab-8
8. 5. ISL-lab-10

(beyond just the pipeline syntax there's usually a couple of lines afterwards which query elements in the pipeline which have to be updated as well).

[tlienart]

I've merged the PR as it was causing issues with the deployment, I'll let you guys adjust the @pipeline stuff and review when you have time but at least the site is back online and uses the latest MLJ.

[tlienart]

all done, thanks @OkonSamuel for the help and fixes!