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BV2182 — why the automatic runoff (and Equal Support)

Generated from bv2182_tg4779_faq_runoff_reversal.yaml — do not edit by hand. Regenerate: python STARVote_LH_tabulation_engine/tools_adam/scripts/build_yaml_pages.py.

Method: STAR (single winner) · 1 seat · Expected winner: Almond

▶ Live on BetterVoting: vote · results ↗ (election tg4779 · test BV2182).

Scenario

A 10-voter STAR election built for the FAQ. Berry is the consensus candidate — broadly liked, so Berry wins the Scoring Round on total stars. But more voters strictly prefer Almond head-to-head, so Almond wins the Automatic Runoff: a clean Runoff Reversal that shows why the second step exists. One voter scores both finalists 5 (Equal Support) — counted, but expressing no preference between the two, so it lands in neither finalist's runoff column. Live results: https://bettervoting.com/tg4779/results

Ballots

Row 1 = candidate names; each later row is one voter's 0–5 scores (a N × prefix = N identical ballots).

Almond,Berry,Cocoa
5,4,1
5,4,1
5,4,1
5,4,1
5,4,0
5,4,0
0,5,2
0,5,2
0,5,2
5,5,0

What the engine says

The count, step by step — the rounds and how the winner is reached:

[Divergence from STAR]
  STAR     = Almond
  Approval = Berry   (differs from STAR)

[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) ---

[STAR Voting]
 Tabulating 10 ballots.
Count × Almond,Berry,Cocoa
    4 ×      5,    4,    1
    3 ×      0,    5,    2
    2 ×      5,    4,    0
    1 ×      5,    5,    0

[STAR Voting: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Berry         -- 44 -- First place
   Almond        -- 35 -- Second place
   Cocoa         -- 10
 Berry and Almond advance.

[STAR Voting: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Almond        -- 6 -- First place
   Berry         -- 3
   Equal Support -- 1
 Almond wins.
   Runoff math:
     10  ballots cast
   −  1  Equal Support (no preference between the two finalists)
     ──
      9  voters with a preference  (majority = 5)
           Almond 6 (67%)  ·  Berry 3 (33%)

[STAR Voting: Winner — STAR Voting Method (single winner)]
 Almond

Full audit — preference matrix, Condorcet, and score distribution

--- Runoff (Preference) Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        * indicates Top 2 Finalist
                 |   * Almond   |  * Berry    |    Cocoa    |
-------------------------------------------------------------
      * Almond > |     ---      | 6 -  1 -  3 | 7 -  0 -  3 |
       * Berry > |  3 -  1 -  6 |    ---      |10 -  0 -  0 |
         Cocoa > |  3 -  0 -  7 | 0 -  0 - 10 |    ---      |

[Condorcet Winner]
  Condorcet Winner: Almond — matches the STAR winner

[Condorcet Loser]
  Condorcet Loser: Cocoa — loses every head-to-head matchup

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Almond     7  0  0  0  0  3  |    35   3.5
Berry      4  6  0  0  0  0  |    44   4.4
Cocoa      0  0  0  3  4  3  |    10   1.0

Everything in one file: the _tabulated mirror (regenerated on every run; every analysis forced on).

Run it yourself:

python STARVote_LH_tabulation_engine/starvote_larry_hastings.py 01_STAR/02_Examples/cases/bv2182_tg4779_faq_runoff_reversal.yaml

See also

More cases in this set: 02a_c3_b1_three-candidates · 02b_c3_b2_three-candidates · 03a_c3_b3_style-bullet-vote · 03b_c3_b3_1_style-protest-vote · 03b_c3_b3_2_expand_style-protest-vote · 03c_c6_b8_style-gallery · 03d_c5_b5_style-gallery-five-more · 04b_c4_b3_display-options-all · 05a_c5_b3_unanimous-ballots · 06a_c9_b3_large-field-equal-support · 06b_c9_runoff-overturns-leader · 09_c4_b100_tennessee-capital · abstentions · bv2184_fyy886_lunch_vote · bv2187_qrw6wb_ann-bob-cal · bv2256_c8h3tb_traditional_style · bv2263_xw23m9_over_50_percent · csv_ambiguity_ex1_c4_b8 · display_options_demo · equal_support_runoff_demo · quorum_demo_c3_b6 · quorum_fail_demo_c3_b6 · same_mean_different_spread_c2_b5 · star_ala_approval · three_winners_cw_score_runoff · vote_splitting · vote_splitting2 · vote_splitting3 · vote_splitting_scenario1_spoiler · vote_splitting_scenario2_bloc_leads · vote_splitting_scenario3_outsider_wins