{
  "schema": "canli.alphac-execution-lab-contract.v1",
  "status": "EDUCATIONAL_INSTRUMENT_NOT_RESEARCH_EVIDENCE",
  "author": "Arhan Canli",
  "published_on": "2026-08-27",
  "claim_boundary": "A synthetic demonstration of how execution assumptions behave. It spends no research hypothesis, writes to no ledger, and produces no ALPHAC performance claim.",
  "method": {
    "series": "driftless geometric random walk with an overnight gap, 750 bars",
    "gap_volatility": 0.004,
    "gap_rationale": "Without a gap the next open IS the decision close, so the single most important comparison on this page collapses to a tie that looks like a finding. The core refuses a series with no gap rather than reporting one.",
    "strategy": "a fixed moving-average crossover, identical across every variant",
    "comparability": "Every variant prices the SAME decision bars. A delayed variant needs an extra bar of runway, so left to itself it would price one fewer decision and its Sharpe would be computed over a different sample."
  },
  "classification": {
    "rule": "Each assumption is measured ALONE against the honest baseline across many independent series. |t| below 2 is indistinguishable from no effect; a worse-share at or above 98 percent is a cost; anything else is a re-timing.",
    "why_isolated": "Measured cumulatively, market impact inherits the delay's variance and is misclassified as a re-timing when it is a pure cost.",
    "kinds": {
      "COST": "reduces the result on essentially every series; small variance, enormous t",
      "RE_TIMING": "changes WHICH prices you get; hurts on average, sign per series close to a coin flip",
      "INDISTINGUISHABLE": "no systematic effect on a series with no edge"
    }
  },
  "defaults": {
    "fast": 14,
    "slow": 34,
    "spread_bps": 5,
    "delay_bars": 1,
    "impact_bps": 8,
    "outage_rate": 0.05,
    "seeds": 200
  },
  "parameter_scaling": {
    "method": "each control varied alone, 300 independent series per setting, mean change in annualised Sharpe",
    "cost_example": {
      "control": "spread_bps",
      "readings": [
        {
          "setting": 5,
          "mean": -0.0326
        },
        {
          "setting": 10,
          "mean": -0.0652
        }
      ],
      "note": "doubles when the parameter doubles, which is what paying for something looks like"
    },
    "re_timing_example": {
      "control": "delay_bars",
      "readings": [
        {
          "setting": 1,
          "mean": -0.0184,
          "t": -1.9
        },
        {
          "setting": 2,
          "mean": -0.0362,
          "t": -2.9
        },
        {
          "setting": 3,
          "mean": -0.0286,
          "t": -2
        },
        {
          "setting": 5,
          "mean": -0.0112,
          "t": -0.6
        }
      ],
      "note": "does not scale, and peaks in the middle. A longer delay is not a bigger cost, it is a different bet."
    }
  },
  "sandbox_safety": [
    "every input is stored in the URL, so a scenario is shareable and reproducible",
    "no write path to any ledger, artifact, broker or published record exists",
    "outputs describe a synthetic series, never an ALPHAC result"
  ],
  "content_hash": "sha256:6fc4f9270beb21aa4038fb2ab02c002e411a9b4eb394dc8549d7ac6ba9489fa0"
}