Nurmi Ex.16 truncated — STAR: unmoved, still B¶

Generated from bv2163_74j6vv_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: B

▶ Live on BetterVoting: vote · results ↗ (election 74j6vv · test BV2163).

Scenario¶

Race 1 of 3 in the RCV-IRV truncation pair, part 2 of 2 (BV2163, bvid 74j6vv; BV-confirmed). Source: Dan S. Felsenthal (2010), Appendix A6, Example 16, due to Nurmi (1999: 63) — see bv2163_74j6vv_irv.yaml for the setup. The same electorate with the 17 truncated ballots scoring only D (everything else 0): A 329, B 373, C 244, D 171 — B still wins the automatic runoff. STAR elects the Condorcet winner B with full ballots (BV2162: 346/407/312/171) and with truncated ones: no truncation incentive on this profile, while the IRV race's winner flips A → B on the same change. Live results: https://bettervoting.com/74j6vv/results

Ballots¶

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

A,B,C,D
33: 5,4,2,1
29: 4,5,2,1
24: 2,4,5,1
17: 0,0,0,5

What the engine says¶

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

[Divergence from STAR]
  STAR                   = B
  Choose-One (Plurality) = A   (differs from STAR)

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

[STAR Voting]
 Tabulating 103 ballots.
Count × A,B,C,D
   33 × 5,4,2,1
   29 × 4,5,2,1
   24 × 2,4,5,1
   17 × 0,0,0,5

[STAR Voting: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   B             -- 373 -- First place
   A             -- 329 -- Second place
   C             -- 244
   D             -- 171
 B and A advance.

[STAR Voting: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   B             -- 53 -- First place
   A             -- 33
   Equal Support -- 17
 B wins.
   Runoff math:
     103  ballots cast
   −  17  Equal Support (no preference between the two finalists)
     ───
      86  voters with a preference  (majority = 44)
           B 53 (62%)  ·  A 33 (38%)

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

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
                 |     * A      |    * B      |      C      |      D      |
---------------------------------------------------------------------------
           * A > |     ---      |33 - 17 - 53 |62 - 17 - 24 |86 -  0 - 17 |
           * B > | 53 - 17 - 33 |    ---      |62 - 17 - 24 |86 -  0 - 17 |
             C > | 24 - 17 - 62 |24 - 17 - 62 |    ---      |86 -  0 - 17 |
             D > | 17 -  0 - 86 |17 -  0 - 86 |17 -  0 - 86 |    ---      |

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

[Condorcet Loser]
  Condorcet Loser: D — 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
A          33  29   0  24   0  17  |   329   3.2
B          29  57   0   0   0  17  |   373   3.6
C          24   0   0  62   0  17  |   244   2.4
D          17   0   0   0  86   0  |   171   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 method_comparisons/felsenthal_paradoxes/cases/bv2163_74j6vv_star.yaml

See also¶