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No-show paradox (2 of 2) — the 8 April fans vote; RCV-IRV hands them their LAST choice

▶ Live on BetterVoting: vote · results ↗ (election 9dhv8y · test BV2175) — 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=April, RCV-IRV=Celia, Ranked Robin=April (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 April
RCV-IRV Celia
Ranked Robin (RCV-RR) April
Approval April
Range / Score April
Condorcet none (cycle)

Flags: none

Source election: method_comparisons/participation_no_show/cases/bv2175_9dhv8y_noshow_showup.yaml · STAR tabulated mirror: bv2175_9dhv8y_noshow_showup_tabulated.txt

3 candidates, 62 ballots.

The ballots

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

Count April Bruno Celia
24 5 2 0
18 0 5 2
20 2 0 5

STAR result (official)

Scoring round (sum of scores): April 160, Bruno 138, Celia 136

Finalists (top two): April and Bruno

Automatic runoff: April 44 vs Bruno 18

STAR winner: April

Full LH STAR engine report:

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
                 |   * April    |  * Bruno    |
-----------------------------------------------
       * April > |     ---      |44 -  0 - 18 |
       * Bruno > | 18 -  0 - 44 |    ---      |

[Divergence from STAR]
  STAR    = April
  RCV-IRV = Celia   (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 62 ballots.
Count × April,Bruno,Celia
   24 ×     5,    2,    0
   20 ×     2,    0,    5
   18 ×     0,    5,    2

[Score Distribution] (how many ballots gave each star rating)
                   Score
Candidate   5   4   3   2   1   0  | Total   Avg
April      24   0   0  20   0  18  |   160   2.6
Bruno      18   0   0  24   0  20  |   138   2.2
Celia      20   0   0  18   0  24  |   136   2.2

Scoring Round
 The two highest-scoring candidates advance to the next round.
   April         -- 160 -- First place
   Bruno         -- 138 -- Second place
   Celia         -- 136
 April and Bruno advance.

Automatic Runoff Round
 The candidate preferred in the most head-to-head matchups wins.
   April         -- 44 -- First place
   Bruno         -- 18
   Equal Support --  0
 April wins.
   Voters with a preference: 62 of 62 (no Equal Support).
   April 44 (71%) vs Bruno 18 (29%); majority = 32.

Winner — STAR Voting Method (single winner)
 April

RCV-IRV — round by round

--- RCV / Instant-Runoff Voting (single winner) ---
 Tabulating 62 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: April, Bruno, Celia
    24 ×   April > Bruno      (5, 2, 0)
    18 ×   Bruno > Celia      (0, 5, 2)
    20 ×   Celia > April      (2, 0, 5)

ROUND 1
Candidate      Votes  Status
-----------  -------  --------
April             24  Hopeful
Celia             20  Hopeful
Bruno             18  Rejected

FINAL RESULT
Candidate      Votes  Status
-----------  -------  --------
Celia             38  Elected
April             24  Rejected
Bruno              0  Rejected


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

--- 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): April, Bruno, Celia
   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 Celia 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 62 ballots (score ballots).

Ballots:
   the ranking Ranked Robin reads ("=" = tied); source scores follow in () per column: April, Bruno, Celia
    24 × April > Bruno > Celia      (5, 2, 0)
    18 × Bruno > Celia > April      (0, 5, 2)
    20 × Celia > April > Bruno      (2, 0, 5)

Round-Robin — every pair, head-to-head (For – Against):
   April  beats Bruno   44 – 18
   Celia  beats April   38 – 24
   Bruno  beats Celia   42 – 20

--- Pairwise (Round-Robin) Matrix ---
Head-to-head / pairwise comparison — the Ranked Robin tally
Legend: For - Equal Support - Against   (row vs column)
          |    April     |   Bruno     |   Celia     |
------------------------------------------------------
  April > |     ---      |44 -  0 - 18 |24 -  0 - 38 |
  Bruno > | 18 -  0 - 44 |    ---      |42 -  0 - 20 |
  Celia > | 38 -  0 - 24 |20 -  0 - 42 |    ---      |

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  April      1–1–0         1     +12  Bruno
    2  Bruno      1–1–0         1      -4  Celia
    3  Celia      1–1–0         1      -8  April

Winner — Ranked Robin (RCV-RR): April
   *** 3 candidates tie for the most wins (April, Bruno, Celia) — 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): April, Bruno, Celia
   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 April 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