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Sincere STAR — the center wins (Beth is the Condorcet winner)

▶ Live on BetterVoting: vote · results ↗ (election 2kcwbw · test BV2221) — an independent tabulator to check the winners below against.

Bucket — IRV_OUTLIER_RR_WITH_STAR: RCV-IRV is the outlier (center squeeze)

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 elects Beth — and so do Ranked Robin and Condorcet, because Beth is the head-to-head (pairwise) winner, beating every rival one-on-one. RCV-IRV instead elects Ana: Beth collects fewer top (first-choice) votes, so IRV eliminates Beth early, and those ballots transfer to Ana. This is the classic center squeeze — the broadly acceptable candidate is knocked out by round-by-round elimination even though a majority prefers them in a direct matchup. Two methods (STAR + RR) against one (RCV-IRV): IRV is the outlier.

Winners by method

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

Flags: none

Source election: method_comparisons/star_5_1_0_challenge/cases/bv2221_2kcwbw_sincere.yaml · STAR tabulated mirror: bv2221_2kcwbw_sincere_tabulated.txt

3 candidates, 100 ballots.

The ballots

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

Count Ana Beth Cole
48 5 3 0
47 0 3 5
5 2 5 0

STAR result (official)

Scoring round (sum of scores): Beth 310, Ana 250, Cole 235

Finalists (top two): Beth and Ana

Automatic runoff: Beth 52 vs Ana 48

STAR winner: Beth

Full LH STAR engine report:

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
                 |    * Ana     |   * Beth    |
-----------------------------------------------
         * Ana > |     ---      |48 -  0 - 52 |
        * Beth > | 52 -  0 - 48 |    ---      |

[Divergence from STAR]
  STAR                   = Beth
  Choose-One (Plurality) = Ana   (differs from STAR)
  RCV-IRV                = Ana   (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 100 ballots.
Count × Ana,Beth,Cole
   48 ×   5,   3,   0
   47 ×   0,   3,   5
    5 ×   2,   5,   0

[Score Distribution] (how many ballots gave each star rating)
                   Score
Candidate   5   4   3   2   1   0  | Total   Avg
Ana        48   0   0   5   0  47  |   250   2.5
Beth        5   0  95   0   0   0  |   310   3.1
Cole       47   0   0   0   0  53  |   235   2.4

Scoring Round
 The two highest-scoring candidates advance to the next round.
   Beth          -- 310 -- First place
   Ana           -- 250 -- Second place
   Cole          -- 235
 Beth and Ana advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   Beth          -- 52 -- First place
   Ana           -- 48
   Equal Support --  0
 Beth wins.
   Voters with a preference: 100 of 100 (no Equal Support).
   Beth 52 (52%) vs Ana 48 (48%); majority = 51.

Winner — STAR Voting Method (single winner)
 Beth

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 100 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: Ana, Beth, Cole
    48 ×   Ana > Beth      (5, 3, 0)
    47 ×   Cole > Beth      (0, 3, 5)
     5 ×   Beth > Ana      (2, 5, 0)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
Ana               48  Hopeful
Cole              47  Hopeful
Beth               5  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Ana               53  Elected
Cole              47  Rejected
Beth               0  Rejected


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

--- 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): Beth
   Outside (2):        Ana, Cole
   One member ⇒ Beth is the Condorcet winner, beating every rival head-to-head.
   RCV-IRV winner Ana is OUTSIDE the Smith set. ✗
      Every member of the set (Beth) beats Ana head-to-head, yet
      RCV-IRV elected Ana anyway. RCV-IRV is not Smith-efficient (nor
      Condorcet-efficient) — this is the shape a center squeeze leaves behind.
   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 100 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: Ana, Beth, Cole
    48 × Ana > Beth > Cole      (5, 3, 0)
    47 × Cole > Beth > Ana      (0, 3, 5)
     5 × Beth > Ana > Cole      (2, 5, 0)

Round-Robin — every pair, head-to-head (For – Against):
   Beth  beats Ana    52 – 48
   Ana   beats Cole   53 – 47
   Beth  beats Cole   53 – 47

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
         |     Ana      |    Beth     |    Cole     |
-----------------------------------------------------
   Ana > |     ---      |48 -  0 - 52 |53 -  0 - 47 |
  Beth > | 52 -  0 - 48 |    ---      |53 -  0 - 47 |
  Cole > | 47 -  0 - 53 |47 -  0 - 53 |    ---      |

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  Beth       2–0–0         2     +10  Ana, Cole
    2  Ana        1–1–0         1      +2  Cole
    3  Cole       0–2–0         0     -12  —

Winner — Ranked Robin (RCV-RR): Beth
   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): Beth
   Outside (2):        Ana, Cole
   One member ⇒ Beth is the Condorcet winner, beating every rival head-to-head.
   Ranked Robin (RCV-RR) winner Beth 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