Circadian Phase / Jet Lag Adjustment Estimator mechanism

Model scope

The instrument should be marked FAIL until the westward formula is corrected to approximately timezone_shift*1.5, input constraints and rounding are specified, and the light-timing output is either formally defined with required inputs or removed. The existing rough population-average and not-medical-advice labels are appropriate but do not resolve the formula error or missing-output definition.

• The written westward formula, timezone_shift/1.5, is not the stated population heuristic of approximately 1.5 days per timezone; it should be timezone_shift*1.5. For eastward travel, division by 1.0 is numerically equivalent to multiplication by 1.0 but obscures the intended rate formulation.
• The formula does not define how direction is represented or validate that direction is eastward or westward.
• The claimed suggested light-exposure timing tips have no formula, timing inputs, or computation defined, so that output cannot be verified from this specification.
• A single timezone count and direction do not determine individualized light timing; travel schedule, destination time, chronotype, sleep timing, and prior light exposure are omitted.

Units and conventions

• timezone_shift is a nonnegative count of time zones crossed, dimensionless but conventionally measured in time-zone intervals.
• The intended heuristic is approximately 1.0 day per timezone eastward and 1.5 days per timezone westward.
• The written formula is evaluated literally in the written-formula test output; the corrected heuristic is shown separately for comparison.
• Direction must be an explicit categorical value such as "east" or "west".
• Estimated days are population-average educational estimates, not a clinical prediction.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "timezone_shift": 3,
    "direction": "east"
  },
  "expected_outputs": {
    "estimated_adjustment_days_written_formula": 3,
    "estimated_adjustment_days_corrected_heuristic": 3
  },
  "working": "Written formula: 3 / 1.0 = 3 days. Corrected heuristic: 3 * 1.0 = 3 days."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The formula itself has no zero-denominator or function-domain failure, but the input convention is underspecified: treating westward travel as a negative timezone shift can produce a negative adjustment duration instead of the intended positive 2 days.

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche5/tranche5-results.json
• BOUNDARY_HAZARD_CATALOG.json