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Center squeeze — STAR elects the consensus (Center)

Generated from center_squeeze_star.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: Center

Scenario

The SAME 27-voter profile as center_squeeze_irv.yaml, translated to 0–5 scores. Center is the broad consensus — the 2nd choice of both poles and the Condorcet winner — but has the fewest first-choices.

RCV-IRV eliminates Center first (too little "core support") and elects the polar Left. STAR counts every ballot in both rounds: Center reaches the runoff on strength of support and wins. The [Divergence from STAR] and [Condorcet Winner] lines below show Choose-One = Left, RCV-IRV = Left, STAR = Center = Condorcet winner (also what Ranked Robin would elect). See 07_Concepts/center_squeeze.md.

Ballots

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

Count:Left,Center,Right
12:5,4,3   # Left > Center > Right
9:3,4,5    # Right > Center > Left
6:4,5,3    # Center > Left > Right

What the engine says

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

[Divergence from STAR]
  STAR                   = Center
  Choose-One (Plurality) = Left   (differs from STAR)
  RCV-IRV                = Left   (differs from STAR)
  Approval               = Left   (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.
  Full round-by-round reports (generated for review):
  RCV-IRV rounds: cases_tabulated/center_squeeze_star_RCV-IRV_tabulated.txt

--- STAR Voting Method (single winner) ---

[STAR Voting]
 Tabulating 27 ballots.
Count × Left,Center,Right
   12 ×    5,     4,    3
    9 ×    3,     4,    5
    6 ×    4,     5,    3

[STAR Voting: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Center        -- 114 -- First place
   Left          -- 111 -- Second place
   Right         --  99
 Center and Left advance.

[STAR Voting: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Center        -- 15 -- First place
   Left          -- 12
   Equal Support --  0
 Center wins.
   Runoff math:
     27  ballots cast
   −  0  Equal Support (no preference between the two finalists)
     ──
     27  voters with a preference  (majority = 14)
           Center 15 (56%)  ·  Left 12 (44%)

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

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
                 |    * Left    |  * Center   |    Right    |
-------------------------------------------------------------
        * Left > |     ---      |12 -  0 - 15 |18 -  0 -  9 |
      * Center > | 15 -  0 - 12 |    ---      |18 -  0 -  9 |
         Right > |  9 -  0 - 18 | 9 -  0 - 18 |    ---      |

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

[Condorcet Loser]
  Condorcet Loser: Right — 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
Left       12   6   9   0   0   0  |   111   4.1
Center      6  21   0   0   0   0  |   114   4.2
Right       9   0  18   0   0   0  |    99   3.7

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 method_comparisons/center_squeeze/cases/center_squeeze_star.yaml

See also

More cases in this set: center_squeeze_irv · center_squeeze_voteline_1d