# Exposure Card: Measurement Regime And Observer Mode

## Possibility

A fixed source can enter different resolvable regimes when the record type,
observer grammar, bandwidth, integration window, and estimator are changed
under matched source conditions.

## Public Question

Does a predeclared observer-mode change produce a reproducible shift in response
quality, record discreteness, or uncertainty structure that survives fixed-source
controls and an unchanged analysis rule?

## Frozen Comparison

- Same declared source and incident-resource envelope
- Same physical target
- Predeclared observer modes
- Fixed preprocessing and estimator per mode
- Matched calibration and reference channel
- Held-out scored records

## Measurements

- response and uncertainty by observer mode;
- bandwidth and integration-window dependence;
- record-discreteness or mode-occupancy statistic;
- calibration and reference-channel agreement;
- source drift, leakage, and post-selection ledger.

## Decisive Branches

- **Persists:** a repeatable observer-mode dependence survives matched-source,
  calibration, leakage, and estimator-contract checks.
- **Closes ordinarily:** the effect follows source drift, bandwidth, filtering,
  calibration, or estimator substitution.
- **Narrow:** a finite regime survives but does not transfer across observer
  modes or windows.

## Next Artifact

A preregistered public result manifest containing the observer contract,
matched-source ledger, held-out summary, and branch decision.

