{
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  "publication_status": "published",
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        "source_kind": "performance_test_fixture",
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        "product_mapping": "services/whatify-api/src/domains/scenarios/when-you-stop/payload.ts",
        "calibration_evidence": "None independently established. Documents existing product assumptions; does not endorse them as a forward-looking forecast.",
        "units": "Decimal annual rates. Means are arithmetic, not compounded/geometric growth rates. Inflation is an annual price-change rate, not an additional real return.",
        "annual_dependence": "Independent annual Gaussian draws; same-year equity/bond correlation zero in this baseline. Inflation is independently drawn.",
        "fee_convention": "Separate annual asset fee applied by the engine; not deducted from the stated return means.",
        "change_policy": "New production defaults require sourced forward-looking assumptions and scenario-matrix review, not fitting a target success rate. This record does not replace product defaults."
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    "transformation": "For each year and series: (value - historical mean) / historical standard deviation * target standard deviation + target mean. Real returns use (1+nominal)/(1+inflation)-1; population std uses ddof=0. Convert adjusted real asset returns back to nominal with adjusted inflation.",
    "controls": [
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      "means_and_spreads matches means and spreads of real stocks, real bonds, and inflation.",
      "Both adjustments preserve standardized annual shapes, row order and correlations.",
      "All cases use the identical fee-free plan and production engine accounting.",
      "block_5 uses random-length blocks averaging five years, with circular wraparound.",
      "IID and block_5 use the same seed across adjustments to retain the same year-index paths."
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    "limitations": [
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      "The means-and-spreads test does not isolate the effect of mean returns alone.",
      "Five-year blocks are a sensitivity choice, not a fitted model of future dependence.",
      "Rolling windows overlap; 69 windows are not 69 independent observations.",
      "One seed per 10000-path case; no test of equality or forecast validation is claimed.",
      "Inflation cancels for this fixed-real-spending tax-free case, not all household models."
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    {
      "start_year": 1986,
      "end_year": 2015,
      "success": true
    },
    {
      "start_year": 1987,
      "end_year": 2016,
      "success": true
    },
    {
      "start_year": 1988,
      "end_year": 2017,
      "success": true
    },
    {
      "start_year": 1989,
      "end_year": 2018,
      "success": true
    },
    {
      "start_year": 1990,
      "end_year": 2019,
      "success": true
    },
    {
      "start_year": 1991,
      "end_year": 2020,
      "success": true
    },
    {
      "start_year": 1992,
      "end_year": 2021,
      "success": true
    },
    {
      "start_year": 1993,
      "end_year": 2022,
      "success": true
    },
    {
      "start_year": 1994,
      "end_year": 2023,
      "success": true
    },
    {
      "start_year": 1995,
      "end_year": 2024,
      "success": true
    },
    {
      "start_year": 1996,
      "end_year": 2025,
      "success": true
    }
  ],
  "limitations": [
    "Descriptive model results, not personal odds or a forecast.",
    "Overlapping historical windows are not independent observations.",
    "Five fixed seeds are examples, not a confidence interval or exhaustive sensitivity study.",
    "No taxes, benefits, fees, healthcare, or changing lifespans in this comparison.",
    "The parametric test uses the app's market settings but removes its 0.4% fee to match the other two fee-free tests. This is not a full product run.",
    "Parametric assumptions are not fitted to this historical dataset; differences include return assumptions, not just sequence generation.",
    "Matching seed IDs do not mean matching market paths across model types.",
    "Pooled random-path rates combine five runs and are not forecast probabilities.",
    "Full engine reproduction requires repository access; the engine is not public."
  ],
  "reproduce": "PYTHONPATH=src python3 scripts/research/bootstrap_vs_rolling.py"
}