Snapshots

A snapshot freezes the market at the instant a signal is filed (and, for airing, at the instant a segment goes on air).

Snapshot {
  priceAtSignal        // price of the side called, bps
  crowdYesAtSignal     // YES share of the crowd at that moment
  crowdNoAtSignal
  marketStatus
  volume
  timeToResolution
  sourcePage           // client and surface the call came from
}

The rule

Capture at write time. Never reconstruct. A snapshot that can be rebuilt later can also be argued about later. Storing reality at the instant of the call is what lets the field record say called it before the move and lets the causal loop measure a broadcast’s footprint instead of narrating it.

Where snapshots are used

• Scoring — timing bonus and closing-line value compare the snapshot to the settled price.
• Air and Move — snapshot at air time, snapshot after; the delta is the broadcast’s footprint. See Air and Move.
• Receipts — a receipt carries the snapshot so it can be shared as a card without a database lookup.