MultinomialNB in Scikit-learn is effective for document classification by modeling word frequencies, and performance can be improved through techniques like TF-IDF transformation and hyperparameter tuning.
Here is the code snippet you can refer to:

In the above code we are using the following key points:
- Uses TF-IDF to convert text data into numerical features while reducing noise.
- Applies the MultinomialNB classifier with Laplace smoothing (alpha).
- Evaluates model performance with a classification report.
Hence, training a MultinomialNB model with TF-IDF transformation and proper hyperparameter tuning significantly enhances document classification accuracy and robustness.