docs: add snippet for creating boosted tree model

[rey-esp]

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Fixes #<issue_number_goes_here> 🦕

[tswast]

No action needed, but something to consider for future: it would be nice to update the prepare section above to work without referencing an index (e.g. when ordering mode = "partial").

We have a few options, but the easiest will be to start with a string column and add (True, "training") as the last in the list of cases.

Aside: we have an issue open (349926559) to allow selecting any column in the dataframe (such as functional_weight, which would be a natural choice in this example) even if its a different type, so long as a True (default) case is provided.

[tswast]

Presumably you ran this code sample and it worked OK? I remember we had some bugs where y had to be a DataFrame not a Series in past, so just double-checking.

[rey-esp]

The code sample seems to run! Not sure if I did it right so here's the colab: https://colab.sandbox.google.com/drive/10jA6zSRiptXWrTkCcmyCT_sYBjLqGJx0?resourcekey=0-0TrIkmDzAJw_F6ONFikwaA#scrollTo=wU367u1SAj3Y

[tswast]

I don't think we should be doing LogisticRegression here. In the SQL we do use model_type='BOOSTED_TREE_CLASSIFIER', but in BigQuery DataFrames we normally use separate Python classes to represent the different model types.

A few ways to discover which class to use:

• Search our code for BOOSTED_TREE_CLASSIFIER
• Google search for boosted trees BigFrames

These should give you some strong hints as to which class to use instead.

[tswast]

Copying this from an internal comment I made for visibility:

Just like scikit-learn, it's one of the "ensemble" methods: https://cloud.google.com/python/docs/reference/bigframes/latest/bigframes.ml.ensemble

Normally we try to use the scikit-learn class names too, but I think we may have added this class before GradientBoostingClassifier was in scikit-learn

[snippet-bot]

Here is the summary of changes.

You are about to add 1 region tag.

• samples/snippets/classification_boosted_tree_model_test.py:42, tag bigquery_dataframes_bqml_boosted_tree_create

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