Comprehensive Data Quality Assessment

Buatlah dashboard yang mengevaluasi overall data quality dengan scoring system.

Metrics

1. completeness_score: 100 - (avg null percentage across key fields)
2. validity_score: percentage of records passing all validations
3. uniqueness_score: percentage of unique emails
4. consistency_score: percentage of standardized city names
5. overall_quality_score: weighted average (completeness: 30%, validity: 30%, uniqueness: 20%, consistency: 20%)
6. quality_grade: A (>=90), B (>=80), C (>=70), D (>=60), F (<60)

Output yang diharapkan: completeness_score, validity_score, uniqueness_score, consistency_score, overall_quality_score, quality_grade