{
  "task_id": "F6-conf-02",
  "sample_start": "2010-01-04",
  "sample_end": "2019-12-31",
  "n_treated": 0,
  "baseline_metric": -0.042851,
  "model_metric": null,
  "effect_estimate": null,
  "effect_ci_low": null,
  "effect_ci_high": null,
  "conclusion": "premise_invalid",
  "feasibility": "infeasible",
  "feasibility_reason": "The file covers 2010-01-04 to 2019-12-31 only; n_treated = 0, so there is no post-cut window and the post-minus-pre difference in mean one-day changes cannot be computed.",
  "data_issues": [
    {
      "issue": "Sample ends 2019-12-31 (README retrieval end_date=2019-12-31), before the 2020-03-04 cut; post_cut = 0 for all rows, so there are zero treated days and no post-cut window.",
      "handling": "Estimand not computable; effect, CI and model RMSE set to null; conclusion premise_invalid. No proxy (e.g. other dates or synthetic data) substituted."
    },
    {
      "issue": "README describes 2020-03-04 both as the announcement date and as 'the first business day after' the announcement (internal inconsistency in flag description).",
      "handling": "Moot because no 2020 rows exist; post_cut used exactly as provided, not redefined."
    },
    {
      "issue": "Missing values: 0; duplicate dates: 0; dates monotonic increasing: True; post_cut disagreements with 'date >= 2020-03-04' rule: 0.",
      "handling": "No cleaning required; recorded for transparency."
    },
    {
      "issue": "Calendar gaps between consecutive rows: max 5 days; 85 gaps longer than a weekend (Canadian holidays / non-publication days).",
      "handling": "Per task rules, one-day changes are taken between consecutive rows regardless of calendar gap."
    }
  ],
  "n_input_rows": {
    "gc5y_daily.csv": 2498
  },
  "n_analysed": null,
  "random_seed": null
}