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Reversal symmetry — STAR, original: B (STAR does not winner=loser here)

Bucket — CYCLE_OR_THREE_WAY: Cycle / three-way split

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

What happens

There is no Condorcet winner — the head-to-head results form a cycle (X beats Y beats Z beats X). With no pairwise anchor the methods split: STAR=B, RCV-IRV=A, Ranked Robin=B (RR breaks the cycle by total margin). No rule is clearly 'right'; a genuinely hard election, not an indictment of any one method.

Winners by method

Method Winner
STAR B
RCV-IRV A
Ranked Robin (RCV-RR) B
Approval B
Range / Score B
Condorcet none (cycle)

Flags: none

Source election: method_comparisons/reversal_symmetry/cases/reversal_star_original.yaml · STAR tabulated mirror: reversal_star_original_tabulated.txt

3 candidates, 24 ballots.

The ballots

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

Count A B C
9 0 5 3
8 5 3 0
7 3 0 5

STAR result (official)

Scoring round (sum of scores): B 69, C 62, A 61

Finalists (top two): B and C

Automatic runoff: B 17 vs C 7

STAR winner: B

Full LH STAR engine report:

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
                 |     * B      |    * C      |
-----------------------------------------------
           * B > |     ---      |17 -  0 -  7 |
           * C > |  7 -  0 - 17 |    ---      |

[Divergence from STAR]
  STAR    = B
  RCV-IRV = A   (differs from STAR)
  Note: no ballots had tied scores, so RCV-IRV vs STAR here is a genuine
        method difference, not a tie-breaking artifact.
  Note: Ranked Robin (RCV-RR) agrees with STAR, so RCV-IRV is the lone
        outlier — the classic center-squeeze signature.

--- STAR Voting Method (single winner) ---
 Tabulating 24 ballots.
Count × A,B,C
    9 × 0,5,3
    8 × 5,3,0
    7 × 3,0,5

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
A          8  0  7  0  0  9  |    61   2.5
B          9  0  8  0  0  7  |    69   2.9
C          7  0  9  0  0  8  |    62   2.6

Scoring Round
 The two highest-scoring candidates advance to the next round.
   B             -- 69 -- First place
   C             -- 62 -- Second place
   A             -- 61
 B and C advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   B             -- 17 -- First place
   C             --  7
   Equal Support --  0
 B wins.
   Voters with a preference: 24 of 24 (no Equal Support).
   B 17 (71%) vs C 7 (29%); majority = 13.

Winner — STAR Voting Method (single winner)
 B

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 24 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: A, B, C
     9 ×   B > C      (0, 5, 3)
     8 ×   A > B      (5, 3, 0)
     7 ×   C > A      (3, 0, 5)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
B                  9  Hopeful
A                  8  Hopeful
C                  7  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
A                 15  Elected
B                  9  Rejected
C                  0  Rejected


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

--- 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 (3 of 3): A, B, C
   Outside (0):        —
   More than one member ⇒ NO Condorcet winner: the top of the tournament is a
   cycle, so the strongest "candidate" is a set, not a person. Which member of
   the set should win is exactly what Minimax / Ranked Pairs / Schulze disagree
   about — see 05_Ranked_Robin/01_Learn/cycle_resolution.md.
   RCV-IRV winner A 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 24 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: A, B, C
     9 × B > C > A      (0, 5, 3)
     8 × A > B > C      (5, 3, 0)
     7 × C > A > B      (3, 0, 5)

Round-Robin — every pair, head-to-head (For – Against):
   A  beats B   15 –  9
   C  beats A   16 –  8
   B  beats C   17 –  7

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
      |      A       |     B       |     C       |
--------------------------------------------------
  A > |     ---      |15 -  0 -  9 | 8 -  0 - 16 |
  B > |  9 -  0 - 15 |    ---      |17 -  0 -  7 |
  C > | 16 -  0 -  8 | 7 -  0 - 17 |    ---      |

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  B          1–1–0         1      +4  C
    2  A          1–1–0         1      -2  B
    3  C          1–1–0         1      -2  A

Winner — Ranked Robin (RCV-RR): B
   *** 3 candidates tie for the most wins (A, B, C) — a Condorcet cycle (no candidate beats all others). Resolved by total margin, then lot order. (This is where Minimax / Ranked Pairs / Schulze differ — see 05_Ranked_Robin/01_Learn/cycle_resolution.md.)

--- 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 (3 of 3): A, B, C
   Outside (0):        —
   More than one member ⇒ NO Condorcet winner: the top of the tournament is a
   cycle, so the strongest "candidate" is a set, not a person. Which member of
   the set should win is exactly what Minimax / Ranked Pairs / Schulze disagree
   about — see 05_Ranked_Robin/01_Learn/cycle_resolution.md.
   Ranked Robin (RCV-RR) winner B 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