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.