Where

The error occurs in the statistics phase, when the ground_truth_label contains a / in the name like: ground_truth_label: "Parameter(0=mod/well,1=poor)"

What happens

When pathlib constructs the path output_dir / "roc-curve_Parameter(0=mod/well,1=poor)=0.svg", the / inside the string is treated as a directory separator.
It tries to open a file inside a non-existent subdirectory roc-curve_Parameter(0=mod/.

Possible fix:

1. Don't allow a / in the ground_truth_label setting and raise an error in every phase
2. Fix all save or export code lines and replace the / with another character like _

In the statistics phase it applies to the following lines of code:

• STAMP/src/stamp/statistics/__init__.py

  Line 295 in c54ce06

  output_dir / f"roc-curve_{ground_truth_label}={true_class}.svg"

• STAMP/src/stamp/statistics/__init__.py

  Line 324 in c54ce06

  output_dir / f"pr-curve_{ground_truth_label}={true_class}.svg"

• STAMP/src/stamp/statistics/categorical.py

  Line 140 in c54ce06

  preds_df.to_csv(outpath / f"{ground_truth_label}_categorical-stats_individual.csv")

• STAMP/src/stamp/statistics/categorical.py

  Line 142 in c54ce06

  stats_df.to_csv(outpath / f"{ground_truth_label}_categorical-stats_aggregated.csv")