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Margins matter — STAR on the same twelve ballots (rank converted 5/3/0)

▶ Live on BetterVoting: vote · results ↗ (election kdjjkq · test BV2251) — an independent tabulator to check the winners below against.

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=Almond, RCV-IRV=Cocoa, Ranked Robin=Berry (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 Almond
RCV-IRV Cocoa
Ranked Robin (RCV-RR) Berry
Approval Berry
Range / Score Berry
Condorcet none (cycle)

Flags: none

Source election: method_comparisons/copeland_vs_borda_margins/cases/margins_star.yaml · STAR tabulated mirror: margins_star_tabulated.txt

3 candidates, 12 ballots.

The ballots

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

Count Almond Berry Cocoa
5 5 3 0
3 0 5 3
2 3 0 5
2 0 3 5

STAR result (official)

Scoring round (sum of scores): Berry 36, Almond 31, Cocoa 29

Finalists (top two): Berry and Almond

Automatic runoff: Berry 5 vs Almond 7

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  | * Berry   |
-----------------------------------------
    * Almond > |    ---     |7 - 0 - 5  |
     * Berry > | 5 - 0 - 7  |   ---     |

[Divergence from STAR]
  STAR     = Almond
  RCV-IRV  = Cocoa   (differs from STAR)
  Approval = Berry   (differs from STAR)
  RCV-RR   = Berry   (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.

[Runoff Reversal]
 - Score Round Winner(s) = (Berry)
 - Runoff Round Winner   = (Almond)
  Candidate Berry earned the highest total score, but
  Candidate Almond 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) ---
 Tabulating 12 ballots.
Count × Almond,Berry,Cocoa
    5 ×      5,    3,    0
    3 ×      0,    5,    3
    2 ×      3,    0,    5
    2 ×      0,    3,    5

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Almond     5  0  2  0  0  5  |    31   2.6
Berry      3  0  7  0  0  2  |    36   3.0
Cocoa      4  0  3  0  0  5  |    29   2.4

Scoring Round
 The two highest-scoring candidates advance to the next round.
   Berry         -- 36 -- First place
   Almond        -- 31 -- Second place
   Cocoa         -- 29
 Berry and Almond advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   Almond        -- 7 -- First place
   Berry         -- 5
   Equal Support -- 0
 Almond wins.
   Voters with a preference: 12 of 12 (no Equal Support).
   Almond 7 (58%) vs Berry 5 (42%); majority = 7.

Winner — STAR Voting Method (single winner)
 Almond

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 12 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: Almond, Berry, Cocoa
     5 ×   Almond > Berry      (5, 3, 0)
     3 ×   Berry > Cocoa      (0, 5, 3)
     2 ×   Cocoa > Almond      (3, 0, 5)
     2 ×   Cocoa > Berry      (0, 3, 5)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
Almond             5  Hopeful
Cocoa              4  Hopeful
Berry              3  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Cocoa              7  Elected
Almond             5  Rejected
Berry              0  Rejected


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

--- 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): Almond, Berry, Cocoa
   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 Cocoa 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 12 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: Almond, Berry, Cocoa
     5 × Almond > Berry > Cocoa      (5, 3, 0)
     3 × Berry > Cocoa > Almond      (0, 5, 3)
     2 × Cocoa > Almond > Berry      (3, 0, 5)
     2 × Cocoa > Berry > Almond      (0, 3, 5)

Round-Robin — every pair, head-to-head (For – Against):
   Almond  beats Berry    7 – 5
   Cocoa   beats Almond   7 – 5
   Berry   beats Cocoa    8 – 4

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
           |  Almond   |  Berry   |  Cocoa   |
----------------------------------------------
  Almond > |    ---    |7 - 0 - 5 |5 - 0 - 7 |
   Berry > | 5 - 0 - 7 |   ---    |8 - 0 - 4 |
   Cocoa > | 7 - 0 - 5 |4 - 0 - 8 |   ---    |

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  Berry      1–1–0         1      +2  Cocoa
    2  Almond     1–1–0         1      +0  Berry
    3  Cocoa      1–1–0         1      -2  Almond

Winner — Ranked Robin (RCV-RR): Berry
   *** 3 candidates tie for the most wins (Almond, Berry, Cocoa) — 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): Almond, Berry, Cocoa
   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 Berry 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