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multi_member_plurality — Block vs. Limited vs. SNTV (LH-only)

The three multi-member plurality methods on one 60/40 electorate (6-voter Home majority, 4-voter Away minority; 3 seats). They differ only in votes per voter, and that alone slides the result from majority sweep to minority-tops-the-poll.

All three are majoritarian at-large methods — whether you want that at all, or a proportional body instead, is the decision that comes first: Electing more than one, simply. The expressive majoritarian alternative to these is Bloc STAR.

Each row links the page — the readable write-up with the ballots and the engine's full count — and the yaml you feed the engine to run it yourself.

Method Votes/voter Winners Home : Away Read · run
Block Voting (plurality-at-large) 3 Ada, Ben, Cal 3 : 0 page · yaml
Limited Voting 2 Ada, Ben, Uma 2 : 1 page · yaml
SNTV 1 Uma, Ada, Ben 2 : 1 (Uma leads) page · yaml

Plus a fourth case on the same family — the majority ceiling (yaml): with k marks per voter no candidate can exceed 1/k of the votes cast, so a unanimous candidate still shows 33.3% at 3 seats. That kills the common "the winner got under 50%, so the vote was split" reading in any multi-seat race — see How often does vote splitting actually happen?.

Confirms our engine's multi-winner Plurality (run_plurality_multi) tabulates the whole family (it auto-detects Block / Limited / SNTV from votes-per-voter).

All BV-confirmed (not exceptions). BV has no method named Block/Limited Voting, but all three are "mark k, top N win" = BV's multi-winner Approval with each voter approving k (full slate = block, k<N = limited, 1 = SNTV). Block & Limited are backed by BV election BV2135 (3x4vrv) — same ballots, same winners; SNTV by the BV2134 governance Bloc Plurality race. The LH yamls carry the Plurality-family teaching label; BV runs them as Approval. Full recipe: running it on BetterVoting.

Full lesson (with Wikipedia + electowiki links): Block, Limited & SNTV — the multi-member plurality family

file: README.md