Test 4: Validating duplicate detection...
Found 24 duplicate groups:
  - Alice Johnson: 1 duplicate(s)
  - Carol White: 1 duplicate(s)
  - Emma Wilson: 1 duplicate(s)
  - Grace Lee: 1 duplicate(s)
  - Iris Taylor: 1 duplicate(s)
  - Karen Thomas: 1 duplicate(s)
  - Monica Jackson: 1 duplicate(s)
  - Olivia Martin: 1 duplicate(s)
  - Quinn Rodriguez: 1 duplicate(s)
  - Steve Walker: 1 duplicate(s)
  - Uma Allen: 1 duplicate(s)
  - Wendy King: 1 duplicate(s)
  - Yara Lopez: 1 duplicate(s)
  - Anna Scott: 1 duplicate(s)
  - Chloe Adams: 1 duplicate(s)
  - Ella Nelson: 1 duplicate(s)
  - Gina Mitchell: 1 duplicate(s)
  - Isla Roberts: 3 duplicate(s)
  - Sarah Johnson: 1 duplicate(s)
  - Michael Brown: 1 duplicate(s)
  - Jennifer Davis: 1 duplicate(s)
  - Robert Wilson: 1 duplicate(s)
  - Lisa Anderson: 1 duplicate(s)
  - Thomas Clark: 1 duplicate(s)
WARNING: 'John Smith' has 3 duplicates, expected 2

✓ All expected duplicate groups found
✓ Match reasons look reasonable
SUCCESS: Duplicate detection validated!