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Summability demo — RCV-IRV district A (B wins)

Generated from irv_district_A.yaml — do not edit by hand. Regenerate: python STARVote_LH_tabulation_engine/tools_adam/scripts/build_yaml_pages.py.

Method: RCV-IRV (Instant Runoff) · 1 seat · Expected winner: B

Scenario

District A of the RCV-IRV summability trio: C is eliminated, C's ballots transfer to B, B wins. Looks precinct-friendly — until you try to combine districts. See irv_combined.yaml: no fixed set of district-level IRV subtotals can be added into the combined answer, because who gets eliminated depends on ALL ballots at once.

Ballots

Each row is one voter's ranking, most-preferred first (N: prefix = N identical ballots).

6:A
4:B
3:C>B>A

What the engine says

Round-by-round Sankey diagram: each candidate's votes as a band, and where the votes of an eliminated candidate transferred to.

Where the votes went. Band thickness is votes; a band leaving an eliminated candidate lands on whoever that ballot ranked next, or on inactive if it ranked nobody who was left.

The count, step by step — the rounds and how the winner is reached:

--- RCV / Instant-Runoff Voting (single winner) ---
  Summability demo — RCV-IRV district A (B wins)
 Tabulating 13 ballots (ranked ballots).

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
A                  6  Hopeful
B                  4  Hopeful
C                  3  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
B                  7  Elected
A                  6  Rejected
C                  0  Rejected


Winner(s) — RCV / Instant-Runoff Voting (single winner)
  B

Full audit — preference matrix, Condorcet, and score distribution

--- Smith Set (the generalized Condorcet winner) ---
The smallest group whose every member beats every candidate outside it —
the honest answer to "who is even in contention?".
   Smith set (1 of 3): B
   Outside (2):        A, C
   One member ⇒ B is the Condorcet winner, beating every rival head-to-head.
   RCV-IRV winner B is INSIDE the Smith set. ✓
      Not guaranteed — RCV-IRV is not Smith-efficient — but it holds here.
   More: 07_Concepts/topics/smith_set.md

Everything in one file: the _tabulated mirror (regenerated on every run; every analysis forced on).

Run it yourself:

python STARVote_LH_tabulation_engine/starvote_larry_hastings.py method_comparisons/summability_demo/cases/irv_district_A.yaml

See also

More cases in this set: irv_combined · irv_district_B · rr_combined · rr_district_A · rr_district_B · star_combined · star_district_A · star_district_B