Fictional practice data

Read ../DATA_DICTIONARY.md before analyzing these files. There is no real personal or operational information here.

• shipments_raw.csv: intentionally imperfect export, 248 rows; use for the cleaning exercise.
• shipments_clean.csv: 240 validated fictional shipments; use for descriptive exploration and storytelling.
• checklist_trial.csv: 40 independent simulated people, one task each; use for the separate randomized inference example.

Do not join the trial to the shipment data. Blank satisfaction is a nonresponse, not zero. Keep IDs as text and leave the CSVs unchanged during practice. Store your own analysis separately. Instructor/reference numerical outputs are in ../outputs/; attempt exercises before reading them.