docs: add section for XGBClassifier

Author: TomeHirata

docs/source/get_started.rst

@@ -153,4 +153,13 @@ To compute QTE, we use "predict_qte" method. The confidence band is computed by
    :alt: QTE of adjusted estimator
    :height: 300px
    :width: 450px
-   :align: center
+   :align: center
+
+You can use any model with "predict_proba" or "predict" method to adjust the distribution function estimation. For example, the following code use XGBoost classifier to estimate the conditional distribution.
+
+.. code-block:: python
+
+  import xgboost as xgb
+  estimator = dte_adj.AdjustedDistributionEstimator(xgb.XGBClassifier(), folds=3)
+  estimator.fit(X, D, Y)
+  cdf = estimator.predict(1, locations)

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "dte_adj"
-version = "0.1.2"
+version = "0.1.3"
 description = "This is a Python library for a research paper 'Estimating Distributional Treatment Effects in Randomized Experiments: Machine Learning for Variance Reduction'"
 readme = "README.md"
 requires-python = ">=3.10"