Section risk screening — methodology

This page documents how the composite score per polling section is built: what each of the six signals measures, the thresholds we apply, and how they are combined into a single 0–100 reading.

The six signals

  • Recount delta — statistical departure between the first and second tally.
  • Flash-memory mismatch — discrepancies between the two protocols.
  • Invalid-ballot share — sections significantly above the municipal median.
  • Additional voters — share of voters added on top of the initial roll.
  • Vote concentration — Herfindahl–Hirschman index across parties.
  • Peer-section outliers — z-score against neighboring sections in the same settlement.

For the live screen see Section-level risk screening.

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Recent analysis

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