{
  "study_id": "pm25-health-v2",
  "track": "B",
  "demo": true,
  "claim_class": "method-validation",
  "protocol_sha256": "78b4a0c505bc948ca0b6e19ec0624a603e160850a745491dbc8368e5ac4c78fb",
  "input": {
    "generator": "make_demo_policy_panel",
    "seed": 20260720,
    "rows": 1280,
    "note": "Synthetic validation fixture; not empirical health evidence"
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  "software": {
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    "linearmodels": "6.1"
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  "sample_audit": {
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      2009,
      2012
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    "value_column": "outcome",
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        "event_time": -4,
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        "control_units": 80,
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      {
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        "standard_error": 0.060282
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      {
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      {
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      {
        "cohort": 2006,
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        "baseline_year": 2005,
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        "estimate": 0.250602,
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        "standard_error": 0.07375
      },
      {
        "cohort": 2009,
        "event_time": 2,
        "target_year": 2011,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.498276,
        "standard_error": 0.074513
      },
      {
        "cohort": 2009,
        "event_time": 3,
        "target_year": 2012,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.597975,
        "standard_error": 0.091944
      },
      {
        "cohort": 2009,
        "event_time": 4,
        "target_year": 2013,
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      {
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        "event_time": 5,
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        "baseline_year": 2008,
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        "estimate": 0.786387,
        "standard_error": 0.081678
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      {
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        "target_year": 2009,
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        "estimate": 0.090688,
        "standard_error": 0.063947
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        "event_time": -2,
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        "treated_units": 20,
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        "estimate": 0.051622,
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      {
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        "baseline_year": 2011,
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        "estimate": 0.298449,
        "standard_error": 0.088334
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        "control_units": 20,
        "estimate": 0.308885,
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      {
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        "event_time": 2,
        "target_year": 2014,
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        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.576135,
        "standard_error": 0.077497
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      {
        "cohort": 2012,
        "event_time": 3,
        "target_year": 2015,
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        "treated_units": 20,
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        "estimate": 0.719491,
        "standard_error": 0.090885
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    ],
    "event_time": [
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        "event_time": -4,
        "estimate": -0.000249,
        "standard_error": 0.037273,
        "ci95_low": -0.073304,
        "ci95_high": 0.072806,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -3,
        "estimate": 0.012708,
        "standard_error": 0.031567,
        "ci95_low": -0.049162,
        "ci95_high": 0.074578,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -2,
        "estimate": 0.017588,
        "standard_error": 0.035321,
        "ci95_low": -0.05164,
        "ci95_high": 0.086817,
        "cohorts": 3,
        "treated_unit_weight": 60
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      {
        "event_time": 0,
        "estimate": 0.234568,
        "standard_error": 0.041445,
        "ci95_low": 0.153336,
        "ci95_high": 0.315801,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 1,
        "estimate": 0.286663,
        "standard_error": 0.039084,
        "ci95_low": 0.210059,
        "ci95_high": 0.363266,
        "cohorts": 3,
        "treated_unit_weight": 60
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      {
        "event_time": 2,
        "estimate": 0.499419,
        "standard_error": 0.041085,
        "ci95_low": 0.418892,
        "ci95_high": 0.579947,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 3,
        "estimate": 0.652309,
        "standard_error": 0.048043,
        "ci95_low": 0.558145,
        "ci95_high": 0.746474,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 4,
        "estimate": 0.749114,
        "standard_error": 0.053463,
        "ci95_low": 0.644325,
        "ci95_high": 0.853902,
        "cohorts": 2,
        "treated_unit_weight": 40
      },
      {
        "event_time": 5,
        "estimate": 0.809412,
        "standard_error": 0.050971,
        "ci95_low": 0.709509,
        "ci95_high": 0.909314,
        "cohorts": 2,
        "treated_unit_weight": 40
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    ],
    "diagnostics": {
      "pretrend_intervals_include_zero": true,
      "pretrend_cells": 3,
      "post_cells": 6
    },
    "post_average": {
      "estimate": 0.508496,
      "standard_error": 0.018435,
      "ci95_low": 0.472364,
      "ci95_high": 0.544628
    },
    "uncertainty_note": "Cell-level difference-in-differences standard errors with cohort-size aggregation. Production studies must also use unit-cluster bootstrap or a design-specific robust estimator."
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  "exposure_first_stage": {
    "value_column": "exposure",
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        "event_time": -4,
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        "standard_error": 0.107235
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        "estimate": 0.024628,
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      {
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        "estimate": -0.198959,
        "standard_error": 0.102912
      },
      {
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        "event_time": 0,
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        "estimate": -3.77502,
        "standard_error": 0.163098
      },
      {
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        "event_time": 1,
        "target_year": 2007,
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        "treated_units": 20,
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        "estimate": -4.66512,
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        "treated_units": 20,
        "control_units": 60,
        "estimate": -5.625075,
        "standard_error": 0.139959
      },
      {
        "cohort": 2006,
        "event_time": 3,
        "target_year": 2009,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -6.239517,
        "standard_error": 0.170351
      },
      {
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        "event_time": 4,
        "target_year": 2010,
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        "treated_units": 20,
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        "estimate": -7.112747,
        "standard_error": 0.166345
      },
      {
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        "event_time": 5,
        "target_year": 2011,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -8.068853,
        "standard_error": 0.150467
      },
      {
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        "event_time": -4,
        "target_year": 2005,
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        "treated_units": 20,
        "control_units": 60,
        "estimate": 0.014382,
        "standard_error": 0.146898
      },
      {
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        "event_time": -3,
        "target_year": 2006,
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        "estimate": -0.055063,
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        "event_time": -2,
        "target_year": 2007,
        "baseline_year": 2008,
        "treated_units": 20,
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        "estimate": 0.207063,
        "standard_error": 0.195878
      },
      {
        "cohort": 2009,
        "event_time": 0,
        "target_year": 2009,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -3.984878,
        "standard_error": 0.144844
      },
      {
        "cohort": 2009,
        "event_time": 1,
        "target_year": 2010,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -4.694383,
        "standard_error": 0.166446
      },
      {
        "cohort": 2009,
        "event_time": 2,
        "target_year": 2011,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -5.598539,
        "standard_error": 0.187314
      },
      {
        "cohort": 2009,
        "event_time": 3,
        "target_year": 2012,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -6.211139,
        "standard_error": 0.23606
      },
      {
        "cohort": 2009,
        "event_time": 4,
        "target_year": 2013,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -7.264584,
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      },
      {
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        "event_time": 5,
        "target_year": 2014,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -7.886559,
        "standard_error": 0.217144
      },
      {
        "cohort": 2012,
        "event_time": -4,
        "target_year": 2008,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.025741,
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      {
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        "event_time": -3,
        "target_year": 2009,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.096289,
        "standard_error": 0.210514
      },
      {
        "cohort": 2012,
        "event_time": -2,
        "target_year": 2010,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.018028,
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      },
      {
        "cohort": 2012,
        "event_time": 0,
        "target_year": 2012,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -3.926767,
        "standard_error": 0.216629
      },
      {
        "cohort": 2012,
        "event_time": 1,
        "target_year": 2013,
        "baseline_year": 2011,
        "treated_units": 20,
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        "estimate": -4.64433,
        "standard_error": 0.204016
      },
      {
        "cohort": 2012,
        "event_time": 2,
        "target_year": 2014,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -5.364665,
        "standard_error": 0.217153
      },
      {
        "cohort": 2012,
        "event_time": 3,
        "target_year": 2015,
        "baseline_year": 2011,
        "treated_units": 20,
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        "estimate": -6.285244,
        "standard_error": 0.211159
      }
    ],
    "event_time": [
      {
        "event_time": -4,
        "estimate": -0.04195,
        "standard_error": 0.089361,
        "ci95_low": -0.217098,
        "ci95_high": 0.133198,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -3,
        "estimate": -0.042241,
        "standard_error": 0.091032,
        "ci95_low": -0.220664,
        "ci95_high": 0.136182,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -2,
        "estimate": -0.003308,
        "standard_error": 0.096074,
        "ci95_low": -0.191614,
        "ci95_high": 0.184997,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 0,
        "estimate": -3.895555,
        "standard_error": 0.102474,
        "ci95_low": -4.096404,
        "ci95_high": -3.694705,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 1,
        "estimate": -4.667944,
        "standard_error": 0.097974,
        "ci95_low": -4.859973,
        "ci95_high": -4.475915,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 2,
        "estimate": -5.529426,
        "standard_error": 0.10637,
        "ci95_low": -5.737911,
        "ci95_high": -5.320942,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 3,
        "estimate": -6.2453,
        "standard_error": 0.119876,
        "ci95_low": -6.480257,
        "ci95_high": -6.010343,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 4,
        "estimate": -7.188665,
        "standard_error": 0.133461,
        "ci95_low": -7.450248,
        "ci95_high": -6.927083,
        "cohorts": 2,
        "treated_unit_weight": 40
      },
      {
        "event_time": 5,
        "estimate": -7.977706,
        "standard_error": 0.132091,
        "ci95_low": -8.236604,
        "ci95_high": -7.718809,
        "cohorts": 2,
        "treated_unit_weight": 40
      }
    ],
    "diagnostics": {
      "pretrend_intervals_include_zero": true,
      "pretrend_cells": 3,
      "post_cells": 6
    },
    "post_average": {
      "estimate": -5.709214,
      "standard_error": 0.046482,
      "ci95_low": -5.800318,
      "ci95_high": -5.61811
    },
    "uncertainty_note": "Cell-level difference-in-differences standard errors with cohort-size aggregation. Production studies must also use unit-cluster bootstrap or a design-specific robust estimator."
  },
  "negative_control": {
    "value_column": "negative_control",
    "comparison_group": "Never-treated or not-yet-treated at both baseline and target year",
    "baseline": "One year before each cohort's treatment start",
    "cell_estimates": [
      {
        "cohort": 2006,
        "event_time": -4,
        "target_year": 2002,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 80,
        "estimate": -0.071282,
        "standard_error": 0.067828
      },
      {
        "cohort": 2006,
        "event_time": -3,
        "target_year": 2003,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 80,
        "estimate": -0.070158,
        "standard_error": 0.066071
      },
      {
        "cohort": 2006,
        "event_time": -2,
        "target_year": 2004,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 80,
        "estimate": -0.056893,
        "standard_error": 0.071091
      },
      {
        "cohort": 2006,
        "event_time": 0,
        "target_year": 2006,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 60,
        "estimate": -0.140133,
        "standard_error": 0.081019
      },
      {
        "cohort": 2006,
        "event_time": 1,
        "target_year": 2007,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 60,
        "estimate": -0.037376,
        "standard_error": 0.07765
      },
      {
        "cohort": 2006,
        "event_time": 2,
        "target_year": 2008,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 60,
        "estimate": 0.02012,
        "standard_error": 0.06732
      },
      {
        "cohort": 2006,
        "event_time": 3,
        "target_year": 2009,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.159757,
        "standard_error": 0.083746
      },
      {
        "cohort": 2006,
        "event_time": 4,
        "target_year": 2010,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.046051,
        "standard_error": 0.067266
      },
      {
        "cohort": 2006,
        "event_time": 5,
        "target_year": 2011,
        "baseline_year": 2005,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.130604,
        "standard_error": 0.089569
      },
      {
        "cohort": 2009,
        "event_time": -4,
        "target_year": 2005,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 60,
        "estimate": 2.9e-05,
        "standard_error": 0.069524
      },
      {
        "cohort": 2009,
        "event_time": -3,
        "target_year": 2006,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 60,
        "estimate": -0.065231,
        "standard_error": 0.060382
      },
      {
        "cohort": 2009,
        "event_time": -2,
        "target_year": 2007,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 60,
        "estimate": -0.03116,
        "standard_error": 0.048843
      },
      {
        "cohort": 2009,
        "event_time": 0,
        "target_year": 2009,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": -0.055685,
        "standard_error": 0.066987
      },
      {
        "cohort": 2009,
        "event_time": 1,
        "target_year": 2010,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.058739,
        "standard_error": 0.069828
      },
      {
        "cohort": 2009,
        "event_time": 2,
        "target_year": 2011,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.042111,
        "standard_error": 0.06499
      },
      {
        "cohort": 2009,
        "event_time": 3,
        "target_year": 2012,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.051771,
        "standard_error": 0.089667
      },
      {
        "cohort": 2009,
        "event_time": 4,
        "target_year": 2013,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.034648,
        "standard_error": 0.089228
      },
      {
        "cohort": 2009,
        "event_time": 5,
        "target_year": 2014,
        "baseline_year": 2008,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -0.102521,
        "standard_error": 0.080456
      },
      {
        "cohort": 2012,
        "event_time": -4,
        "target_year": 2008,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.024866,
        "standard_error": 0.072719
      },
      {
        "cohort": 2012,
        "event_time": -3,
        "target_year": 2009,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.009102,
        "standard_error": 0.086296
      },
      {
        "cohort": 2012,
        "event_time": -2,
        "target_year": 2010,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 40,
        "estimate": 0.012843,
        "standard_error": 0.08816
      },
      {
        "cohort": 2012,
        "event_time": 0,
        "target_year": 2012,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.014043,
        "standard_error": 0.075945
      },
      {
        "cohort": 2012,
        "event_time": 1,
        "target_year": 2013,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -0.063824,
        "standard_error": 0.097565
      },
      {
        "cohort": 2012,
        "event_time": 2,
        "target_year": 2014,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": -0.104935,
        "standard_error": 0.085074
      },
      {
        "cohort": 2012,
        "event_time": 3,
        "target_year": 2015,
        "baseline_year": 2011,
        "treated_units": 20,
        "control_units": 20,
        "estimate": 0.045634,
        "standard_error": 0.090559
      }
    ],
    "event_time": [
      {
        "event_time": -4,
        "estimate": -0.015463,
        "standard_error": 0.040445,
        "ci95_low": -0.094735,
        "ci95_high": 0.06381,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -3,
        "estimate": -0.042096,
        "standard_error": 0.041444,
        "ci95_low": -0.123325,
        "ci95_high": 0.039134,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": -2,
        "estimate": -0.02507,
        "standard_error": 0.041112,
        "ci95_low": -0.105649,
        "ci95_high": 0.05551,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 0,
        "estimate": -0.060592,
        "standard_error": 0.043229,
        "ci95_low": -0.145321,
        "ci95_high": 0.024137,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 1,
        "estimate": -0.014154,
        "standard_error": 0.047638,
        "ci95_low": -0.107524,
        "ci95_high": 0.079217,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 2,
        "estimate": -0.014235,
        "standard_error": 0.042155,
        "ci95_low": -0.096858,
        "ci95_high": 0.068389,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 3,
        "estimate": -0.020784,
        "standard_error": 0.050831,
        "ci95_low": -0.120414,
        "ci95_high": 0.078845,
        "cohorts": 3,
        "treated_unit_weight": 60
      },
      {
        "event_time": 4,
        "estimate": 0.04035,
        "standard_error": 0.055871,
        "ci95_low": -0.069158,
        "ci95_high": 0.149858,
        "cohorts": 2,
        "treated_unit_weight": 40
      },
      {
        "event_time": 5,
        "estimate": -0.116563,
        "standard_error": 0.060199,
        "ci95_low": -0.234553,
        "ci95_high": 0.001428,
        "cohorts": 2,
        "treated_unit_weight": 40
      }
    ],
    "diagnostics": {
      "pretrend_intervals_include_zero": true,
      "pretrend_cells": 3,
      "post_cells": 6
    },
    "post_average": {
      "estimate": -0.030108,
      "standard_error": 0.020105,
      "ci95_low": -0.069512,
      "ci95_high": 0.009297
    },
    "uncertainty_note": "Cell-level difference-in-differences standard errors with cohort-size aggregation. Production studies must also use unit-cluster bootstrap or a design-specific robust estimator."
  },
  "decision": {
    "pretrend_pass": true,
    "exposure_first_stage_pass": true,
    "negative_control_pass": true,
    "identification_checks_pass": true,
    "conclusion": "The deterministic validation fixture recovers the simulated exposure reduction and health improvement while leaving the negative-control outcome near zero. This validates the workflow, not a real PM2.5 causal claim."
  }
}