# Data audit (P1)

File: data/schools.csv, SHA-256 0f1d8378fff2f0898762feaa08dd94d9ad04156dad6330572d98997c9005c88a (matches bundle.json).

• 1000 rows (+header), 4 columns: school_id int, student_id int, treated int (0/1), score float (points).
• No dates in data. Missing values: 0 in all columns. Full-row duplicates: 0; duplicated student_id: 0.
• 40 schools (ids 100–139), each exactly 25 students (balanced). treated constant within every school; 20 treated, 20 control schools.
• score range 35.72–64.17, mean 50.80, sd 4.48; no implausible values.
• Information-availability: only input is schools.csv; no violations.
• Exclusions: none (see out/exclusions.csv).