Summability demo — STAR district B (Oak wins — a runoff reversal)¶

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

Method: STAR (single winner) · 1 seat · Expected winner: Oak

Official tie-break (lot) order: Maple > Oak > Pine — consulted only if every deterministic tiebreaker stays tied (how the ladder works).

Scenario¶

District B of the STAR summability trio — the other half of the star_combined electorate. Publish its per-candidate score sums and pairwise matrix, add them to district A's, and you have the combined election's entire count: that's summability, and it's what makes STAR precinct-friendly and cheap to audit. Contrast the irv_* files, whose district tallies cannot be combined.

Ballots¶

Row 1 = candidate names; each later row is one voter's 0–5 scores (a N × prefix = N identical ballots).

Maple, Oak, Pine
1,5,4
0,5,3
4,0,5

What the engine says¶

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

[Divergence from STAR]
  STAR     = Oak
  Approval = Pine   (differs from STAR)

[Runoff Reversal]
 - Score Round Winner(s) = (Pine)
 - Runoff Round Winner   = (Oak)
  Candidate Pine earned the highest total score, but
  Candidate Oak won the automatic runoff — not a malfunction,
  STAR working as designed: the runoff elects the finalist preferred
  by the majority (of voters with a preference).

--- STAR Voting Method (single winner) ---

[STAR Voting]
 Tabulating 3 ballots.
Maple,Oak,Pine
    1,  5,   4
    0,  5,   3
    4,  0,   5

[STAR Voting: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Pine          -- 12 -- First place
   Oak           -- 10 -- Second place
   Maple         --  5
 Pine and Oak advance.

[STAR Voting: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Oak           -- 2 -- First place
   Pine          -- 1
   Equal Support -- 0
 Oak wins.
   Runoff math:
     3  ballots cast
   − 0  Equal Support (no preference between the two finalists)
     ─
     3  voters with a preference  (majority = 2)
           Oak 2 (67%)  ·  Pine 1 (33%)

[STAR Voting: Winner — STAR Voting Method (single winner)]
 Oak

Full audit — preference matrix, Condorcet, and score distribution¶

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
               |    Maple   |  * Oak    |  * Pine   |
-----------------------------------------------------
       Maple > |    ---     |1 - 0 - 2  |0 - 0 - 3  |
       * Oak > | 2 - 0 - 1  |   ---     |2 - 0 - 1  |
      * Pine > | 3 - 0 - 0  |1 - 0 - 2  |   ---     |

[Condorcet Winner]
  Condorcet Winner: Oak — matches the STAR winner

[Condorcet Loser]
  Condorcet Loser: Maple — loses every head-to-head matchup

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Maple      0  1  0  0  1  1  |     5   1.7
Oak        2  0  0  0  0  1  |    10   3.3
Pine       1  1  1  0  0  0  |    12   4.0

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/star_district_B.yaml

Summability demo — STAR district B (Oak wins — a runoff reversal)¶

Scenario¶

Ballots¶

What the engine says¶

Full audit — preference matrix, Condorcet, and score distribution¶

See also¶