Lecture+6+-+STV%2C+SNTV%2C+_+start+of+MMS+10.19.10 - SNTV...

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SNTV
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Single nontransferable vote in multi-member
districts (SNTV/MMD
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Where used? ) ex Japan
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Why “MMD” part important?
If it was just sntv without mmd.. Would be
same thing as plurality in a single member district
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How’s it work?
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“Single”
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Each voter casts one ballot for a candidate
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“nontransferable”
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Each vote stays with that candidate
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Different from STV
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“MMD”

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More SNTV/MMD
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Is this PR?
No it is not because - -not intended but can be .. Not mechanism where votes and
seats are intended to match

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An Example
District 1 (M = 4)
Candidate A (JSP): 80,000 votes
Candidate B (LDP): 19,999
Candidate C (LDP): 19,000
Candidate D (LDP): 18,500
Candidate E (JSP): 18,000
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How many seats does each party win?
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Who wins those seats? A-D get seats- top get
seats up to # of seats availble

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What Guarantees a Seat?
Vote % needed to guarantee seat
=
(100/(M+1)) + 1 vote
what gurantees one a seat- most def get a seat- can get one w/o though
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What is this equation?
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Droop quota
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This merely helps predict what you need
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It’s not a requirement in Japan
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United States Congress example:
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(100/[1+1]) + 1 vote = 50% + 1 vote

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Examples
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M=3
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25% (+ 1 vote) m+1==== 3+1/ 100
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M=4
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20% (+ 1 vote)
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M=5
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16.7% (+ 1 vote)
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As district magnitude goes up.. Can get a seat
with a small share of the vote

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But can win with many fewer as well!
District 1 (M = 5)- can win a seat with 10%-
can help individuals w/o a lot of votes geat
seat
Candidate A (JSP): 20,000 votes (20.9%)
Candidate B (LDP): 19,999 (20.9%)
Candidate C (LDP): 19,000 (19.9%)
Candidate D (LDP): 18,500 (19.4%)
Candidate E (JSP): 10,000 (10.5%)
Candidate F (LDP): 8,000 (8.4%)

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Effects of SNTV/MMD
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Party Fragmentation
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Why?
Small share of the vote and still get a seat, say you are a small party
contesting a election.. 5 seat district, can run and still get a seat– others have to
make an alliance– get parties converging together and creating a new party
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Intraparty competition
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Why
? 130 districts m=500, say big party and want to get majority of seats, have to win
a least two seats per district. Need 251 to get majority. Have to run more than 2 in every
distict– end up competing with one another . Competition is witin parties
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Factions-
biggest party in japan.. Broken up– factions that divide up the party
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Emphasis on candidate rather than party
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Why?