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Data Quality Testing Lab
Inspect ML training data for missing values, duplicates, outliers, and other quality issues that could compromise model performance.
Your Mission
You are a QA tester reviewing a loan approval dataset that will be used to train an ML model. Your job is to find data quality issues that could affect model performance. Click on any suspicious cell to report an issue.
Approval rules: The model is expected to approve applicants with credit score > 650 AND income > $50,000.
Issue Types
Missing ValueDuplicate RecordOutlier/AnomalyMislabeled DataData Type ErrorSample BiasFormatting IssueInvalid Value
Found Issues:0
| ID | Name | Age | Income | Credit Score | City | Approved |
|---|---|---|---|---|---|---|
| 1 | Alice Johnson | 28 | $94,424 | 579 | Chicago | No |
| 2 | Bob Smith | 49 | $36,688 | 624 | New York | No |
| 3 | Carlos Garcia | 24 | $100,467 | 706 | Los Angeles | Yes |
| 4 | Diana Chen | 23 | $91,218 | 579 | New York | No |
| 5 | Emma Wilson | 49 | — | 735 | New York | Yes |
| 6 | Frank Brown | 50 | $63,958 | 523 | New York | No |
| 7 | Grace Lee | 43 | $60,248 | 790 | Houston | Yes |
| 8 | Grace Lee | 43 | $60,248 | 790 | Houston | Yes |
| 9 | Grace Lee | 43 | $60,248 | 790 | Houston | Yes |
| 10 | James Anderson | 67 | $102,004 | 735 | Chicago | Yes |
| 11 | Karen White | 57 | $41,746 | 715 | Phoenix | No |
| 12 | Liam Harris | 49 | $101,213 | — | Los Angeles | No |
| 13 | Maria Rodriguez | 63 | $59,917 | 563 | New York | No |
| 14 | Nathan Clark | 30 | $65,424 | 696 | Los Angeles | Yes |
| 15 | Olivia Lewis | 150 | $116,176 | 603 | Phoenix | No |
Showing rows 1–15 of 50