Is there a way to do a Regression in Catboost for a Gamma distributed response variable?

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I'm working on an Insurance model and I'd like to run Severity and Frequency models using the Catboost gradient boosting algorithm. The problem is that according to the literature, a Severity model assumes a Gamma distributed response variable, while according to the Catboost documentation, a Gamma objective model is not supported. Is there a way utilize one of the existing objectives (e.g. Poisson or Tweedie), to achieve that?

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Andreyn On

Yes, you can set the variance_power (p symbol in the literature) parameter of Tweedie distribution to 2 to get a Gamma distribution.

example:

CatBoostRegressor(loss_function='Tweedie:variance_power=2', n_estimators=500, silent=True)