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Monotonicity — STAR counterpart (AFTER — X still wins)

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=X, RCV-IRV=Z, Ranked Robin=X (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 X
RCV-IRV Z
Ranked Robin (RCV-RR) X
Approval X
Range / Score X
Condorcet none (cycle)

Flags: none

Source election: method_comparisons/monotonicity/cases/monotonicity_star_after.yaml · STAR tabulated mirror: monotonicity_star_after_tabulated.txt

3 candidates, 34 ballots.

The ballots

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

Count X Y Z
16 5 3 0
8 0 5 3
10 3 0 5

STAR result (official)

Scoring round (sum of scores): X 110, Y 88, Z 74

Finalists (top two): X and Y

Automatic runoff: X 26 vs Y 8

STAR winner: X

Full LH STAR engine report:

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
                 |     * X      |    * Y      |
-----------------------------------------------
           * X > |     ---      |26 -  0 -  8 |
           * Y > |  8 -  0 - 26 |    ---      |

[Divergence from STAR]
  STAR    = X
  RCV-IRV = Z   (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 34 ballots.
Count × X,Y,Z
   16 × 5,3,0
   10 × 3,0,5
    8 × 0,5,3

[Score Distribution] (how many ballots gave each star rating)
                   Score
Candidate   5   4   3   2   1   0  | Total   Avg
X          16   0  10   0   0   8  |   110   3.2
Y           8   0  16   0   0  10  |    88   2.6
Z          10   0   8   0   0  16  |    74   2.2

Scoring Round
 The two highest-scoring candidates advance to the next round.
   X             -- 110 -- First place
   Y             --  88 -- Second place
   Z             --  74
 X and Y advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   X             -- 26 -- First place
   Y             --  8
   Equal Support --  0
 X wins.
   Voters with a preference: 34 of 34 (no Equal Support).
   X 26 (76%) vs Y 8 (24%); majority = 18.

Winner — STAR Voting Method (single winner)
 X

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 34 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: X, Y, Z
    16 ×   X > Y      (5, 3, 0)
     8 ×   Y > Z      (0, 5, 3)
    10 ×   Z > X      (3, 0, 5)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
X                 16  Hopeful
Z                 10  Hopeful
Y                  8  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Z                 18  Elected
X                 16  Rejected
Y                  0  Rejected


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

--- 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): X, Y, Z
   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 Z 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 34 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: X, Y, Z
    16 × X > Y > Z      (5, 3, 0)
     8 × Y > Z > X      (0, 5, 3)
    10 × Z > X > Y      (3, 0, 5)

Round-Robin — every pair, head-to-head (For – Against):
   X  beats Y   26 –  8
   Z  beats X   18 – 16
   Y  beats Z   24 – 10

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
      |      X       |     Y       |     Z       |
--------------------------------------------------
  X > |     ---      |26 -  0 -  8 |16 -  0 - 18 |
  Y > |  8 -  0 - 26 |    ---      |24 -  0 - 10 |
  Z > | 18 -  0 - 16 |10 -  0 - 24 |    ---      |

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  X          1–1–0         1     +16  Y
    2  Y          1–1–0         1      -4  Z
    3  Z          1–1–0         1     -12  X

Winner — Ranked Robin (RCV-RR): X
   *** 3 candidates tie for the most wins (X, Y, Z) — 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): X, Y, Z
   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 X 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