VetsLearn — Analyze data & support decisions — 02: Clean data without hiding your decisions
Revision 2026-10-03; fictional training fixture.

OUTCOME
Create a reversible cleaning record.

INDEPENDENT TASK
Independent rows: J1, Item A, quantity 2; J1, Item A, quantity 2 repeated; J2, Item A, quantity 3; J3, Item B, quantity -1. Rule: IDs identify unique issues; quantities must be positive. Produce accepted and review tables.

STEPS
1. Keep the original four rows.
2. Remove only the repeated J1 under the supplied rule.
3. Quarantine J3 and compute the accepted quantity.

ACCEPTANCE CRITERIA
- Accepted quantity is 5 from J1 and J2.
- Item A repetition alone is not a duplicate key.
- Preserve J3 for review and report incomplete coverage.

EXPLAIN YOUR APPROACH
Which cleaning rule depends on business meaning rather than formatting?

Keep your artifact, corrections, evidence and limitations yourself.
Self-review is not independent assessment. No paid model calls are required.
Review notes: /paths/analysis/02/#practice