Week 9 (Elections)

Question 1

What is an electoral system?

Answer 1

The set of rules that govern how votes are cast, and seats allocated, at elections.

Question 2

What are the three elements of electoral systems?

Answer 2

• Electoral formula (plurality/majority, PR, mixed systems)
• Ballot structure (party lists, candidates… one vote, ranking of preferences)
• District magnitude (how many representatives elected for a district)

Question 3

How do majoritarian/plurality systems work?

Answer 3

They use single-member constituencies.

• FPTP - each voter casts one vote; candidate with greatest number of votes is elected
• AV/IRV - voters rank candidates, with candidates eliminated and votes transferred
• Two-round systems - if no candidate wins a majority; the top candidates advance to a second round, in which a plurality is needed to win

Ex: UK, USA (both FPTP), Australia (AV/IRV), France (two-round).

Question 4

How do PR systems work?

(Give examples of the three categories (closed-list, open-list and STV)).

Answer 4

PR systems use multi-member constituencies, and attempt to give parties roughly the same proportion of seats as votes.

• PR systems can vary in district magnitude. Netherlands = 150 MPs per district; Spain = roughly 7 MPs per district.
• In party-list PR, citizens vote for an electoral list associated with a party; these lists can be closed or open.
• In STV, citizens rank candidates; candidates are eliminated and votes transferred until the required number of candidates is elected.

Ex: Spain (closed-list), Brazil (open-list), Ireland (STV).

Question 5

How do mixed electoral systems work?

Answer 5

A combination of majoritarian and proportional systems.

• Voters cast two votes: one for a candidate and one for a party.
• Most mixed systems are compensatory, using compensatory seats to ensure overall proportionality. Others are parallel, with no attempt to rectify the over-representation of larger parties in the constituency vote.

Ex: Germany; Scottish devolved parliament.

Question 6

What is Duverger’s law?

Answer 6

Duverger’s law holds that majoritarian voting systems tend to favour two-party systems, while proportional voting systems tend to favour multi-party systems.