Riverbend mayor, one machine's readings altered: evidence account

The contest

Title: Riverbend mayor, one machine's readings altered

Candidates: Ames, Bell, Cruz.

Records in this count: 60.

Ballot file: comparison-altered-machine

Source: Synthetic committed CVRs. No real election was counted.

Sixty ballots, twenty to a precinct, one reading machine to a precinct. The papers hold Ames 22, Bell 28, Cruz 10. reader-3 recorded ten of its Bell papers as Ames, so the machine readings report Ames 32, Bell 18, Cruz 10. Each row is one physical ballot; `paper` is present only where the paper differs from the machine reading. This is a fixture, not a sealed container.

Where the records sat:

One stack of 60 records. There is no ballot manifest of sealed containers.

No container custody was supplied.

What was configured

Configuration version: comparison-altered-machine-plurality-v1-under-schulze.

Configuration fingerprint (SHA-256): e93e022180f5a1f0752233f335ce2d30bf8a33d474fe75befe14831e56848c8f.

Counting rule: Schulze.

Ballot rules used: Two or more marks at one rank end the ballot there; 2 ranks in a row left blank end the ballot; a candidate marked again lower down counts as a rank left blank.

Ballot file: comparison-altered-machine. A third party with this file can rerun the count.

Audit: none. No seed was used.

Configured audit risk limit: 10%.

Plain-language configuration (check against statute intent):

Configuration version: comparison-altered-machine-plurality-v1-under-schulze

Fingerprint (SHA-256): e93e022180f5a1f0752233f335ce2d30bf8a33d474fe75befe14831e56848c8f

Election: Riverbend mayor, one machine's readings altered, counted under Schulze (beatpath)

A demonstration configuration over committed fixture records, counting the same ballots under another rule. No audit ran under it, and no real election was counted under it.

Contests and candidates:

Riverbend mayor, one machine's readings altered (mayor): Ames; Bell; Cruz.

Counting rule: Schulze (beatpath).

Tiebreak: not used under this counting rule.

Ballot rules (how marks become a ranking):

Two or more marks at one rank: the ballot counts up to that rank and no further.

A candidate marked again lower down: that rank counts as a rank left blank.

2 ranks in a row left blank: the ballot counts up to there and no further.

A mark for anyone not on the ballot: a mark, so the rank is not blank, but never a vote.

Audit risk limit: 10%. A risk-limiting audit that runs under this configuration stops when the sample confirms the outcome at that limit, or sends the contest to a full hand count.

How a ballot is counted and how an audit stops are fixed by this version. Changing any of the lines above requires a new version id.

The count

What follows is the counting account under Schulze, including every intermediate step.

What was counted

Ballots in this count: 60.

Ballots from: Synthetic committed CVRs. No real election was counted.

Sixty ballots, twenty to a precinct, one reading machine to a precinct. The papers hold Ames 22, Bell 28, Cruz 10. reader-3 recorded ten of its Bell papers as Ames, so the machine readings report Ames 32, Bell 18, Cruz 10. Each row is one physical ballot; `paper` is present only where the paper differs from the machine reading. This is a fixture, not a sealed container.

How the marks on a ballot were read:

Two or more marks at one rank: the ballot counts up to that rank and no further.

A candidate marked again lower down: that rank counts as a rank left blank.

2 ranks in a row left blank: the ballot counts up to there and no further.

A mark for anyone not on the ballot: a mark, so the rank is not blank, but never a vote.

The rankings the ballots form, and how many ballots form each. A candidate a ranking does not name is ranked last on those ballots.

Head to head

Every candidate is set against every other. A ballot counts in a matchup when it ranks one of the two above the other. A candidate a ballot never ranks is ranked last on that ballot, tied with every other candidate it never ranks, so such a ballot has no preference between them.

Schulze beatpaths

For every ordered pair, take the strongest chain of pairwise wins connecting them (the weakest link in a chain is its strength; the strongest such chain wins).

A candidate's score is how many opponents they beat on those strengths.

Outcome

Beatpath wins: Ames 2; Bell 1; Cruz 0.

Ames is elected under Schulze: more strongest beatpaths favor Ames than any other candidate.

Records with no mark, by contest and by machine

At the close of polls, the share of records with no mark in each contest, by contest and by machine. Leaving a contest blank is a voter's right; an outlier below is a question about the ballot or the machine, not a verdict.

The audit

No audit ran.

What was found

No audit ran, so there are no sample findings.

Custody: none supplied. No container custody chain was recorded or verified.

Why it stopped

Decision: no audit.

No audit ran.

Outcome status: preliminary. Software tallies stay preliminary until an audit on the record confirms them or a full hand count of the record replaces them.