Tennessee capital, four ways — same ballots; Memphis, Knoxville or Nashville by count (BV2155)¶

Generated from bv2155_cphxpt_tennessee_four_ways.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: Nashville

▶ Live on BetterVoting: vote · results ↗ (election cphxpt · test BV2155).

Scenario¶

The classic Tennessee state-capital example. One set of ballots; Plurality picks MEMPHIS, RCV-IRV picks KNOXVILLE, and Condorcet + STAR pick NASHVILLE (the central compromise that beats everyone head-to-head). Nobody is being strategic — these are sincere ballots. The whoops belongs to Plurality and IRV here. Scores are a simple geographic-distance spatial model. Level 201. Fairness note in the lesson. Live results: https://bettervoting.com/cphxpt/results (all races LH<->BV confirmed). Lesson: bv2155_cphxpt_tennessee_four_ways.md Live on BetterVoting: https://bettervoting.com/cphxpt/results (BV-confirmed; STAR is race 1).

Ballots¶

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

Memphis, Nashville, Chattanooga, Knoxville
42 × 5, 2, 1, 0      # Memphis voters (far west)
26 × 1, 5, 3, 2      # Nashville voters (central)
15 × 0, 3, 5, 4      # Chattanooga voters (southeast)
17 × 0, 3, 4, 5      # Knoxville voters (east)

What the engine says¶

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

[Divergence from STAR]
  STAR                   = Nashville
  Choose-One (Plurality) = Memphis   (differs from STAR)
  RCV-IRV                = Knoxville   (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/bv2155_cphxpt_tennessee_four_ways_RCV-IRV_tabulated.txt

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

[STAR Voting]
 Tabulating 100 ballots.
Count × Memphis,Nashville,Chattanooga,Knoxville
   42 ×       5,        2,          1,        0
   26 ×       1,        5,          3,        2
   17 ×       0,        3,          4,        5
   15 ×       0,        3,          5,        4

[STAR Voting: Scoring Round]
 The two highest-scoring candidates advance to the next round.
   Nashville     -- 310 -- First place
   Chattanooga   -- 263 -- Second place
   Memphis       -- 236
   Knoxville     -- 197
 Nashville and Chattanooga advance.

[STAR Voting: Automatic Runoff Round]
 The candidate preferred in the most head-to-head matchups wins.
   Nashville     -- 68 -- First place
   Chattanooga   -- 32
   Equal Support --  0
 Nashville wins.
   Runoff math:
     100  ballots cast
   −   0  Equal Support (no preference between the two finalists)
     ───
     100  voters with a preference  (majority = 51)
           Nashville 68 (68%)  ·  Chattanooga 32 (32%)

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

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
                    |      Memphis    |  * Nashville   | * Chattanooga  |    Knoxville   |
------------------------------------------------------------------------------------------
          Memphis > |       ---       | 42 -  0 - 58   | 42 -  0 - 58   | 42 -  0 - 58   |
      * Nashville > |  58 -  0 - 42   |      ---       | 68 -  0 - 32   | 68 -  0 - 32   |
    * Chattanooga > |  58 -  0 - 42   | 32 -  0 - 68   |      ---       | 83 -  0 - 17   |
        Knoxville > |  58 -  0 - 42   | 32 -  0 - 68   | 17 -  0 - 83   |      ---       |

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

[Condorcet Loser]
  Condorcet Loser: Memphis — loses every head-to-head matchup — elected by Choose-One (Plurality)!

[Score Distribution] (how many ballots gave each star rating)
                     Score
Candidate     5   4   3   2   1   0  | Total   Avg
Memphis      42   0   0   0  26  32  |   236   2.4
Nashville    26   0  32  42   0   0  |   310   3.1
Chattanooga  15  17  26   0  42   0  |   263   2.6
Knoxville    17  15   0  26   0  42  |   197   2.0

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 method_comparisons/paradoxes_and_whoops/cases/bv2155_cphxpt_tennessee_four_ways.yaml

Tennessee capital, four ways — same ballots; Memphis, Knoxville or Nashville by count (BV2155)¶

Scenario¶

Ballots¶

What the engine says¶

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

See also¶