# Troubleshooting ## `ValueError: numpy.dtype size changed` This is usually a NumPy/Pandas binary compatibility issue. ```bash pip install --upgrade --force-reinstall "numpy>=1.26.4" "pandas>=2.1.4" ``` Restart your Python kernel/session after reinstalling. ## `Scores column not found` Run `predict_scores()` before `match()`. ```python matcher.fit_scores(...) matcher.predict_scores() matcher.match(...) ``` ## `FileNotFoundError` for dataset path Use a repo-relative path: ```python pd.read_csv("misc/loan.csv") ``` ## No matches found Usually threshold is too strict or groups are weakly overlapping. - increase `threshold` - try a different `model_type` - inspect score distributions with `plot_scores()` ## Jupyter kernel issues in notebooks If your notebook kernel name is unavailable, switch to an existing kernel (`python3`) and rerun cells.