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Voting styles — low-score ballots

Bucket — APPROVAL_OR_MINOR: Only Approval differs

Generated by STARVote_LH_tabulation_engine/tools_adam/scripts/build_divergence_index.py — rebuilt from the election file; do not hand-edit.

What happens

STAR, RCV-IRV and Ranked Robin all agree on Almond. Only Approval differs, electing Choco: Approval counts every score of 3–5 as one equal 'approve' and ignores intensity, rewarding Choco's breadth of acceptability over Almond's stronger but more concentrated support. A threshold story about Approval, not a STAR-vs-IRV teaching case.

Winners by method

Method Winner
STAR Almond
RCV-IRV Almond
Ranked Robin (RCV-RR) Almond
Approval Choco
Range / Score Almond
Condorcet Almond

Flags: none

Source election: 01_STAR/02_Examples/cases/03b_c3_b3_1_style-protest-vote.yaml · STAR tabulated mirror: 03b_c3_b3_1_style-protest-vote_tabulated.txt

3 candidates, 3 ballots.

The ballots

Each row is a group of identical score ballots (0 = no support, 5 = max).

Count Choco Almond Vanilla
2 0 1 0
1 0 0 1

STAR result (official)

Scoring round (sum of scores): Almond 2, Vanilla 1, Choco 0

Finalists (top two): Almond and Vanilla

Automatic runoff: Almond 2 vs Vanilla 1

STAR winner: Almond

Full LH STAR engine report:

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

[Divergence from STAR]
  STAR     = Almond
  Approval = Choco   (differs from STAR)

--- STAR Voting Method (single winner) ---
 Tabulating 3 ballots.
Count × Choco,Almond,Vanilla
    2 ×     0,     1,      0
    1 ×     0,     0,      1

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Choco      0  0  0  0  0  3  |     0   0.0
Almond     0  0  0  0  2  1  |     2   0.7
Vanilla    0  0  0  0  1  2  |     1   0.3

Scoring Round
 The two highest-scoring candidates advance to the next round.
   Almond        -- 2 -- First place
   Vanilla       -- 1 -- Second place
   Choco         -- 0
 Almond and Vanilla advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   Almond        -- 2 -- First place
   Vanilla       -- 1
   Equal Support -- 0
 Almond wins.
   Voters with a preference: 3 of 3 (no Equal Support).
   Almond 2 (67%) vs Vanilla 1 (33%); majority = 2.

Winner — STAR Voting Method (single winner)
 Almond

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 3 ballots (converted from score ballots; 0 = unranked, equal scores broken by candidate priority).

Ballots:
   the ranking RCV-IRV reads (0 = unranked, equal scores broken by priority);
   the source score ballot follows in () per column: Choco, Almond, Vanilla
     2 ×   Almond      (0, 1, 0)
     1 ×   Vanilla      (0, 0, 1)

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Almond             2  Elected
Vanilla            1  Rejected
Choco              0  Rejected


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

--- 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): Almond
   Outside (2):        Choco, Vanilla
   One member ⇒ Almond is the Condorcet winner, beating every rival head-to-head.
   RCV-IRV winner Almond is INSIDE the Smith set. ✓
      Not guaranteed — RCV-IRV is not Smith-efficient — but it holds here.
   More: 07_Concepts/topics/smith_set.md

NOTE: a generated cross-method view of the STAR ballots, for comparison only — not the official STAR result.

Ranked Robin (RCV-RR) — every pair, head-to-head

--- Ranked Robin (RCV-RR / Copeland) Method (single winner) ---
 Tabulating 3 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: Choco, Almond, Vanilla
     2 × Almond > Choco=Vanilla      (0, 1, 0)
     1 × Vanilla > Choco=Almond      (0, 0, 1)

Round-Robin — every pair, head-to-head (For – Against):
   Almond   beats Choco     2 – 0
   Vanilla  beats Choco     1 – 0
   Almond   beats Vanilla   2 – 1

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
            |   Choco   | Almond   | Vanilla  |
-----------------------------------------------
    Choco > |    ---    |0 - 1 - 2 |0 - 2 - 1 |
   Almond > | 2 - 1 - 0 |   ---    |2 - 0 - 1 |
  Vanilla > | 1 - 2 - 0 |1 - 0 - 2 |   ---    |

Win–loss record — Copeland score = wins + ½·ties (highest score wins; ties broken by total margin, then lot order):
    #  Candidate  W–L–T  Copeland  Margin  Beats
    1  Almond     2–0–0         2      +3  Vanilla, Choco
    2  Vanilla    1–1–0         1      +0  Choco
    3  Choco      0–2–0         0      -3  —

Winner — Ranked Robin (RCV-RR): Almond
   beats every opponent head-to-head — the Condorcet winner.

--- 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): Almond
   Outside (2):        Choco, Vanilla
   One member ⇒ Almond is the Condorcet winner, beating every rival head-to-head.
   Ranked Robin (RCV-RR) winner Almond is INSIDE the Smith set. ✓
      Guaranteed: Ranked Robin (Copeland) is Smith-efficient — every member of
      the set outscores every outsider, so the top of the win–loss table is
      always inside the set, however the tie among them is then broken.
   More: 07_Concepts/topics/smith_set.md