diff --git a/explainableai/core.py b/explainableai/core.py
index 638daf2..93302ac 100644
--- a/explainableai/core.py
+++ b/explainableai/core.py
@@ -62,7 +62,7 @@ def _preprocess_data(self):
 
         categorical_transformer = Pipeline(steps=[
             ('imputer', SimpleImputer(strategy='constant', fill_value='missing')),
-            ('onehot', OneHotEncoder(handle_unknown='ignore', sparse=False))
+            ('onehot', OneHotEncoder(handle_unknown='ignore', sparse_output=False))
         ])
 
         self.preprocessor = ColumnTransformer(