# Verification checks (P4)

• Clean re-run: results.json byte-identical: PASS; analytic.csv & exclusions.csv md5 identical: PASS
• analytic rows == n_analysed: PASS
• n_firms: PASS
• no rating col: PASS
• cols: PASS
• ledger arithmetic: PASS
• ledger chain: PASS
• ledger start/end: PASS
• raw-removed=analysed: PASS
• se>0: PASS
• CI contains beta: PASS
• r2 in [0,1]: PASS
• default_rate matches: PASS
• no year 2022 (outcome unknown): PASS
• no dup firm-year: PASS
• no NaN: PASS
• numpy beta matches: PASS
• manual CR1 SE matches: PASS
• LPM beta plausible magnitude vs baseline rate: PASS
• Note: cluster SE uses statsmodels CR1 small-sample correction G/(G-1)*(N-1)/(N-K), replicated manually.