BV131 — Guido example (Bloc STAR): seat 1 is a hidden lot-decided tie¶

Generated from bv131_guido_bloc.yaml — do not edit by hand. Regenerate: python STARVote_LH_tabulation_engine/tools_adam/scripts/build_yaml_pages.py.

Method: Bloc STAR (multi-winner, majoritarian) · 2 seats · Expected winners: Cand2, Cand3

Official tie-break (lot) order: Cand2 > Cand1 > Cand3 — consulted only if every deterministic tiebreaker stays tied (how the ladder works).

Scenario¶

The LH reference for BetterVoting test BV131 ("Guido example", real election kbh3d9). The sheet marks it Passed, but seat 1 is actually a PERFECT lot-decided tie — the Bloc analog of jfk7pd.

Bloc STAR, 3 candidates, 2 seats. Totals: Cand1=6, Cand2=6, Cand3=5. - Seat 1: Cand1 and Cand2 tie at 6 and advance. In the runoff they tie 1-1; score is 6-6; five-star is 1-1 each. Every deterministic rung ties, so the LOT decides. BetterVoting drew Cand2 at random (its round-0 logs: runoff_tied -> runoff_score_tie -> runoff_five_star_tie -> runoff_random -> Cand2). This file pins the lot order [Cand2, Cand1, Cand3] to REPRODUCE BV's Cand2. - Seat 2: remove Cand2 -> Cand1 (6) and Cand3 (5) advance; Cand3 wins the runoff 2-1. Winners: Cand2, Cand3 (reproducing BV).

Two findings worth flagging: 1. Non-reproducible, like jfk7pd: with the column-order fallback (no lot order) LH would elect Cand1 for seat 1, not Cand2 — same ballots, different winner, decided only by the tie-break order (cf. #1063). 2. Reporting mislabel: BV's top-level tieBreakType is "none", even though its own round-0 tieBreakType is "random". A reader of the summary can't tell that seat 1 was a coin toss.

Ballots¶

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

Cand1,Cand2,Cand3
1,5,2
0,0,1
5,1,2

What the engine says¶

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

[Divergence from STAR]
  STAR               = Cand2
  RCV-IRV            = Cand3   (differs from STAR)
  RCV-RR (Condorcet) = Cand3   (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) sides with RCV-IRV, so STAR is the outlier
        here — STAR need not elect the Condorcet candidate.
  Full round-by-round reports (generated for review):
  RCV-IRV rounds: cases_tabulated/bv131_guido_bloc_RCV-IRV_tabulated.txt
  RCV-RR round-robin: cases_tabulated/bv131_guido_bloc_RCV-RR_tabulated.txt

--- Bloc STAR Voting Method (2 winners) ---

[Bloc STAR]
 Tabulating 3 ballots to fill 2 seats.
Cand1,Cand2,Cand3
    1,    5,    2
    0,    0,    1
    5,    1,    2

[Bloc STAR: Round 1: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Cand1         -- 6 -- First place
   Cand2         -- 6 -- Second place
   Cand3         -- 5
 Cand1 and Cand2 advance.

[Bloc STAR: Round 1: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Cand1         -- 1 -- Tied for first place
   Cand2         -- 1 -- Tied for first place
   Equal Support -- 1
 There's a two-way tie for first.

[Bloc STAR: Round 1: Automatic Runoff Round: First tiebreaker]
 The highest-scoring candidate wins.
   Cand1         -- 6 -- Tied for first place
   Cand2         -- 6 -- Tied for first place
 There's still a two-way tie for first.

[Bloc STAR: Round 1: Automatic Runoff Round: Second tiebreaker]
 The candidate with the most votes of score 5 wins.
   Cand1         -- 1 -- Tied for first place
   Cand2         -- 1 -- Tied for first place
 There's still a two-way tie for first.

*(Ties are resolved by choosing the tied candidate with the highest-priority official lot number.)*
    Lot-number priority order: ['Cand2', 'Cand1', 'Cand3']

[Tiebreaker: Lot Number Priority]
  Tie among: ['Cand1', 'Cand2']
  Resolved: ['Cand2'] (selected by lot-number priority).

[Lot-decided tie — rare]
  ⚠ The ballots did not break this tie: the deterministic rungs
    (pairwise / score, then five-star) all came back equal, so the
    pre-published LOT order chose among the tied candidates — the
    result here was set by lot, not by the votes. Usually the
    "dead rung": no tied candidate held a score-5 vote (five-star
    counts fives, not fours). Verify the tied candidates' 5-counts.

──────────────────────────────────────────────────

[Bloc STAR: Round 2: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Cand1         -- 6 -- First place
   Cand3         -- 5 -- Second place
 Cand1 and Cand3 advance.

[Bloc STAR: Round 2: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Cand3         -- 2 -- First place
   Cand1         -- 1
   Equal Support -- 0
 Cand3 wins.
   Runoff math:
     3  ballots cast
   − 0  Equal Support (no preference between the two finalists)
     ─
     3  voters with a preference  (majority = 2)
           Cand3 2 (67%)  ·  Cand1 1 (33%)

[Bloc STAR: Winners — Bloc STAR Voting Method (2 winners)]
 Cand2
 Cand3

Full audit — preference matrix, Condorcet, and score distribution¶

--- Preference Matrix ---
Head-to-head / pairwise comparison
Legend: For - Equal Support - Against
        Informational only — not part of the 2-winner count below,
        so no Top-2 finalists are marked.
               |    Cand1   |   Cand2   |   Cand3   |
-----------------------------------------------------
       Cand1 > |    ---     |1 - 1 - 1  |1 - 0 - 2  |
       Cand2 > | 1 - 1 - 1  |   ---     |1 - 0 - 2  |
       Cand3 > | 2 - 0 - 1  |2 - 0 - 1  |   ---     |

[Condorcet Winner]
  Condorcet Winner: Cand3 — STAR elected Cand2 instead (Cand3 was eliminated in the scoring round)

[Condorcet Loser]
  No strict Condorcet loser; jointly weak Condorcet losers: Cand1, Cand2 (winless — pairwise ties) — Cand2 elected by STAR, Choose-One (Plurality), Approval!

[Score Distribution] (how many ballots gave each star rating)
                Score
Candidate  5  4  3  2  1  0  | Total   Avg
Cand1      1  0  0  0  1  1  |     6   2.0
Cand2      1  0  0  0  1  1  |     6   2.0
Cand3      0  0  0  2  1  0  |     5   1.7

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 02_STAR_Bloc/02_Examples/cases/bv131_guido_bloc.yaml

BV131 — Guido example (Bloc STAR): seat 1 is a hidden lot-decided tie¶

Scenario¶

Ballots¶

What the engine says¶

Full audit — preference matrix, Condorcet, and score distribution¶

See also¶