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Condorcet's 1788 rebuttal to Borda — STAR elects the Condorcet winner

▶ Live on BetterVoting: vote · results ↗ (election khcwm4 · test BV2250) — an independent tabulator to check the winners below against.

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

Winners by method

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

Flags: none

Source election: method_comparisons/borda_condorcet_1788/cases/condorcet_1788_star.yaml · STAR tabulated mirror: condorcet_1788_star_tabulated.txt

3 candidates, 11 ballots.

The ballots

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

Count Peter Paul James
4 5 3 0
3 0 5 3
2 3 5 0
2 3 0 5

STAR result (official)

Scoring round (sum of scores): Paul 37, Peter 32, James 19

Finalists (top two): Paul and Peter

Automatic runoff: Paul 5 vs Peter 6

STAR winner: Peter

Full LH STAR engine report:

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
               |  * Peter   |  * Paul   |
-----------------------------------------
     * Peter > |    ---     |6 - 0 - 5  |
      * Paul > | 5 - 0 - 6  |   ---     |

[Divergence from STAR]
  STAR                   = Peter
  Choose-One (Plurality) = Paul   (differs from STAR)
  Approval               = Paul   (differs from STAR)

[Runoff Reversal]
 - Score Round Winner(s) = (Paul)
 - Runoff Round Winner   = (Peter)
  Candidate Paul earned the highest total score, but
  Candidate Peter 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 11 ballots.
Count × Peter,Paul,James
    4 ×     5,   3,    0
    3 ×     0,   5,    3
    2 ×     3,   5,    0
    2 ×     3,   0,    5

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Peter      4  0  4  0  0  3  |    32   2.9
Paul       5  0  4  0  0  2  |    37   3.4
James      2  0  3  0  0  6  |    19   1.7

Scoring Round
 The two highest-scoring candidates advance to the next round.
   Paul          -- 37 -- First place
   Peter         -- 32 -- Second place
   James         -- 19
 Paul and Peter advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   Peter         -- 6 -- First place
   Paul          -- 5
   Equal Support -- 0
 Peter wins.
   Voters with a preference: 11 of 11 (no Equal Support).
   Peter 6 (55%) vs Paul 5 (45%); majority = 6.

Winner — STAR Voting Method (single winner)
 Peter

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 11 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: Peter, Paul, James
     4 ×   Peter > Paul      (5, 3, 0)
     3 ×   Paul > James      (0, 5, 3)
     2 ×   Paul > Peter      (3, 5, 0)
     2 ×   James > Peter      (3, 0, 5)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
Paul               5  Hopeful
Peter              4  Hopeful
James              2  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Peter              6  Elected
Paul               5  Rejected
James              0  Rejected


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

--- 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): Peter
   Outside (2):        Paul, James
   One member ⇒ Peter is the Condorcet winner, beating every rival head-to-head.
   RCV-IRV winner Peter 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 11 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: Peter, Paul, James
     4 × Peter > Paul > James      (5, 3, 0)
     3 × Paul > James > Peter      (0, 5, 3)
     2 × Paul > Peter > James      (3, 5, 0)
     2 × James > Peter > Paul      (3, 0, 5)

Round-Robin — every pair, head-to-head (For – Against):
   Peter  beats Paul    6 – 5
   Peter  beats James   6 – 5
   Paul   beats James   9 – 2

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
          |   Peter   |  Paul    |  James   |
---------------------------------------------
  Peter > |    ---    |6 - 0 - 5 |6 - 0 - 5 |
   Paul > | 5 - 0 - 6 |   ---    |9 - 0 - 2 |
  James > | 5 - 0 - 6 |2 - 0 - 9 |   ---    |

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  Peter      2–0–0         2      +2  Paul, James
    2  Paul       1–1–0         1      +6  James
    3  James      0–2–0         0      -8  —

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