Multi-member plurality — SNTV (3 seats): the minority tops the poll

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

Method: plurality · 3 seats · Expected winners: Uma, Ada, Ben

Official tie-break (lot) order: Ada > Ben > Cal > Uma > Val > Wren — consulted only if every deterministic tiebreaker stays tied (how the ladder works).

Scenario

One of three races comparing the multi-member plurality family on the SAME 60/40 electorate (LH-only — see the set README). 10 voters, 3 seats: a 6-voter MAJORITY (Home: Ada, Ben, Cal) and a 4-voter MINORITY (Away: Uma).

SNTV (single non-transferable vote): each voter casts exactly ONE vote, no matter how many seats. Vote management decides everything. The majority spreads its 6 votes evenly (2 Ada, 2 Ben, 2 Cal); the minority concentrates all 4 on Uma. So Uma FINISHES FIRST with 4, and the majority's split leaves its candidates on 2 each — Uma plus two Home candidates win, 2-1. The 40% minority earns a seat because SNTV rewards concentrating votes (and punishes over-nominating). This is the majoritarian sweep of Block Voting turned into rough proportionality.

Ballots

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

Ada,Ben,Cal,Uma,Val,Wren
2: 1,0,0,0,0,0
2: 0,1,0,0,0,0
2: 0,0,1,0,0,0
4: 0,0,0,1,0,0

What the engine says

Full report from the _tabulated mirror (regenerated on every run; every analysis forced on):

--- SNTV (single non-transferable vote) — 3 winners ---
 Tabulating 10 ballots (1 vote/voter).

First-choice votes (most votes fill the seats):
   Uma      4  <- Elected
   Ada      2  <- Elected
   Ben      2  <- Elected
   Cal      2
   Val      0
   Wren     0

Winners — SNTV (single non-transferable vote), 3 seats:
   1. Uma   (4 votes)
   2. Ada   (2 votes)
   3. Ben   (2 votes)
   *** the last seat tied on votes (Ben and Cal) — decided by lot order.

Run it yourself:

python STARVote_LH_tabulation_engine/starvote_larry_hastings.py method_comparisons/multi_member_plurality/cases/mmp_sntv.yaml

See also

• Vote splitting (worked set)
• Glossary · all cases by method

More cases in this set: mmp_block_voting · mmp_limited_voting · mmp_majority_ceiling