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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
IDNameAgeIncomeCredit ScoreCityApproved
1Alice Johnson28$94,424579ChicagoNo
2Bob Smith49$36,688624New YorkNo
3Carlos Garcia24$100,467706Los AngelesYes
4Diana Chen23$91,218579New YorkNo
5Emma Wilson49735New YorkYes
6Frank Brown50$63,958523New YorkNo
7Grace Lee43$60,248790HoustonYes
8Grace Lee43$60,248790HoustonYes
9Grace Lee43$60,248790HoustonYes
10James Anderson67$102,004735ChicagoYes
11Karen White57$41,746715PhoenixNo
12Liam Harris49$101,213Los AngelesNo
13Maria Rodriguez63$59,917563New YorkNo
14Nathan Clark30$65,424696Los AngelesYes
15Olivia Lewis150$116,176603PhoenixNo

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