[WIP][New Model] PerpetualBoosting

[LennartPurucker]

This code adds the PerpetualBooster (https://github.com/perpetual-ml/perpetual).

Benchmark TabArena-Full Results

All results: perpetual_boosting.zip
Raw results: https://data.lennart-purucker.com/tabarena/data_PerpetualBoosting.zip

Notes

• I only evaluated the one default config, which already has a lot of open TODOs, before we should try it with HPO.
• The code has a few problems with memory management. This goes so far that I was not able to get one dataset with many categoricals to run at all. So I had to impute one dataset (see the LB impute column)
• Another big problem is that one cannot add a callback for early stopping on external validation data.

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[LennartPurucker]

The authors of PerpetualBoosting have closed the integration issue on their side.
So it is unlikely that the model will receive the updates or integration (with verification by the authors) that is required.

Moreover, as the initial results do not seem promising enough, I am not willing to invest more time into fixing the problems for the integration myself in the near future.

How should we proceed? @Innixma @dholzmueller
Should we still include these results and add some kind of additional tag or column to indicate clearly that this is even more experimental/unverified than our other unverified results?