Social Choice Lecture 12

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Social ChoiceLecture 12

• Carmen Pasca and John Hey

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Voting Systems

• Plan for today to examine actual voting systems
  in use in Europe and to discuss their properties.
• Electoral systems in Europe We examine the rules
  and mechanisms used in democratic elections
  across the parliaments of Europe.
• Elections lie at the heart of representative
  democracy, enacting citizens' rights to have a
  say in by whom they are governed.
• The electoral process is the ultimate symbol and
  act of modern democratic societies.

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Desirable features of voting systems 1

• All electoral systems seek to take account of at
  least some or all of the features on this and the
  following two slides which of these are deemed
  most important tends to shape people's preference
  of electoral system.
• Ensuring a representative parliament parliaments
  should reflect the population that chose it, both
  in terms of political support, but also
  regionally and ethnically.
• Making elections accessible and meaningful
  Voters should feel that their taking part will
  make a difference to the result, or else they
  will increasingly refuse to participate,
  undermining the legitimacy of the results.

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Desirable features of voting systems 2

• Facilitating efficient and stable government. The
  system should make it possible for the government
  of the day to enact legislation, run the economy
  and carry out the other tasks of government. The
  system should also be set up in such a way that
  it does not favour one party at the expense of
  the others.
• Holding the government and representatives
  accountable for their actions. This is one of the
  corner stones of electoral systems. They must
  provide a check on the actions of individuals
  once elected, and provide an opportunity at
  regular intervals to remove those who the
  electorate feel are no longer suitable for office.

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Desirable features of voting systems 3

• Promoting and respecting a parliamentary
  opposition. To be effective, governments also
  need to have an opposition to assess proposals
  critically, speak up for the interests of those
  not represented by the government, and provide
  reassurance to the electorate that there is
  always the possibility of changing governments at
  a later date.
• On the next few slides we discuss the different
  types of voting systems that exist in practice.

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Majoritarian systems

• Majoritarian, or plurality, systems represent the
  oldest and simplest electoral system category,
  based on the principle that whichever candidate
  receives the most votes in a constituency is
  deemed elected.
• The following three slides discuss three
  varieties of majority systems which operate on
  the basis of single-member constituencies.

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'First-past-the-post' (FPTP) or simple majority

• This is the most straightforward electoral
  system, and is found in the UK, USA, Canada and
  India.
• To win, a candidate need only receive one more
  vote than any other candidate. Since a minimum
  threshold (i.e. a minimum level - usually a
  percentage - of the popular vote required for a
  party to be allowed to gain parliamentary
  representation) is rarely a part of this system
  and an absolute majority is not required, the
  winner may still win with a relatively small
  proportion of the vote.

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Second Ballot Majority Runoff or absolute majority

• This system requires a candidate to obtain one
  more vote than half the votes cast in order to be
  elected. If no candidate gets that many votes, a
  second round is held.
• In this system, either a simple majority is
  sufficient in the second round, or a "run-off"
  election is held between the two candidates who
  received the most votes in the first round, also
  along absolute majority lines. France and the
  Ukraine both use variations of this system.

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Alternative Vote

• This system also seeks to ensure that a candidate
  is elected by an absolute majority, but does so
  in a single round using Preferential Voting (i.e.
  expressing a rank order of preferences) instead
  of a two-stage system. Constituents vote for a
  single candidate but indicate, in declining
  order, their preferences for other candidates. If
  none of the candidate gets an absolute majority
  on the first count, the candidate who polled the
  fewest votes is eliminated, and his preferences
  are distributed among the remaining candidates.
  This is repeated until one of the candidates has
  an absolute majority. This is used in Australia
  and for the Irish presidential elections.
• In the UK there will be a referendum in May to
  decide whether this system will be introduced
  there.

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Properties of Majoritarian systems 1

• Majoritarian systems are simple. They do not
  require complex mathematics to produce their
  results and they encourage transparency, since
  votes are easily translated into parliamentary
  seats. Many proportional systems, such as Single
  Transferable Vote, are unattractive in that they
  involve very lengthy and complex calculations.
• The 'winner-takes-all' philosophy behind these
  systems focuses on producing a clear, strong and
  stable body of representatives and government,
  not on mirroring the make-up of the general
  population.

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Properties of Majoritarian systems 2

• Because of the way that majoritarian systems
  disproportionately reward large parties over
  small parties, the leading party is rarely
  required to build a coalition to create a
  government.
• A one-party government (which, one should
  remember, is already a complex coalition of
  interests) is therefore free of the problems that
  can emerge from being involved in a coalition
  which might make it weak government is
  immediately broadly united policy need not be
  diluted as it might in a coalition where a
  partner party may demand policy concessions
  ministerial portfolios can be distributed without
  fear of party political battles or major policy
  cleavages (although other battles will still
  rage) the identity and message of a party in
  government need not be confused, or aggravated,
  by its close association with another party.

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Properties of Majoritarian systems 3

• Just as a majoritarian system tends to create
  strong government, it also tends to lead to a
  strong alternative party, such as in the UK and
  the USA.
• This creates a dynamic political arena where
  government needs to work hard because there is
  always a viable and strong alternative which the
  public can chose to replace them with
• Smaller parties are not effectively represented
  in majoritarian systems can be seen to have some
  advantages. They encourage minority groups to
  integrate into the larger parties, which is
  desirable both for the minority group (which can
  gain the political support for some or all of its
  concerns) and the large group (which gains the
  electoral support of the minority).

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Properties of Majoritarian systems 4

• Different groups are brought together by
  political need which encourages cooperation and
  the creation of parties with 'broad church'
  appeal, rather than division by electoral systems
  which may only serve to highlight differences and
  keep minorities at a distance. It can also serve
  to discourage extremist minority parties from
  gaining parliamentary representation,
• Individual citizens feel that they are part of
  the democratic process through a single
  representative, who is there to help with
  individual or community casework. The election of
  representatives by a proportional system in a
  multi-member constituency (which may even be the
  entire country) would not determine this link.

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Properties of Majoritarian systems 5

• Single-member constituencies which operate in
  majoritarian systems also encourage the linkage
  of an elected representative to a particular
  geographic area and the residents of that area,
  who become his or her constituents. This link
  encourages those elected to prioritise serving
  their constituents above satisfying the party
  hierarchy, since their re-election will depend
  entirely on those same people.
• This link is particularly important in the UK,
  where MPs have always been viewed as
  representatives of a specific area, not of the UK
  as a whole.

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Proportional Systems 1

• While majoritarian systems provide the oldest
  model for electoral systems, proportional
  representation (PR) systems are currently the
  most widely used in Europe. Its focus is on the
  creation of a parliamentary chamber which
  accurately reflects the diverse make-up of an
  electorate. The two main PR system categories are
  Party List and Single Transferable Vote. Both of
  these carry a range of considerations in creating
  representative parliaments.

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Proportional Systems 2

• The size of the constituency (also refered to as
  'district magnitude') is important since it can
  affect how 'accurate' the results reflect a
  general electorate. 'Full PR' considers the whole
  country as a single constituency, with seats
  allocated on a pro rata basis according to the
  number of votes cast. This is considered to yield
  the most 'pure' form of PR. 'Limited PR' sees
  elections taking place in several constituencies,
  and is considered to not produce as accurate a
  snapshot of the population, since the greater the
  number of constituencies (and hence the fewer the
  number of seats available per constituency), the
  harder it is to ensure complete proportionality.

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Proportional Systems 3

• Many systems used include a threshold.
• This aims to reduce the extent to which
  proportionality is taken. By putting in place a
  minimum level of national support required for a
  political party to be allowed to gain
  parliamentary representation, it limits the
  ability for very small parties to gain
  representation. It is understood that the
  electoral threshold had its origin in inter-war
  Germany, as a result of the Weimar Republic's
  concern with extremist groups. Some thresholds
  are nominal, others are so large that it
  challenges the basic idea behind using a PR
  system.

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Proportional Systems 4

• In some countries, political parties not reaching
  the thresholds and getting no seats can
  potentially waste millions of votes. Another
  requirement which some countries (many in central
  and eastern Europe) also have in place is a
  minimum quorum level, which demands that for an
  election to be deemed valid and fully
  representative the turnout must meet or exceed a
  percentage of the electorate.

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Party List system 1

• A Party List system presents multi-member
  constituency electorates with political parties
  putting forward slates or lists of candidates.
• It represents the principal PR system in
  operation, although there are many variations of
  it, based on constituency size (as covered
  above), thresholds and quorums (also examined
  above), rules about whether the electorate can
  have preferences for individuals on party lists,
  whether the Greatest Remainder or Highest Average
  systems are used and which formulas are used
  within them.

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Party List system 2

• Before looking at the Greatest Remainder and
  Highest Average systems, one must cover perhaps
  the most important variant in the Party List
  system the ability of the voter to influence the
  party list. The ability of the voter to influence
  the party lists acknowledges that voters will
  often have preferences for individual candidates
  within party lists and that they might also wish
  to satisfy those preferences regardless of what
  the party hierarchies have put in front of them.
  The extent to which a voter can have choice in a
  Party List PR system is determined by one of the
  following variations. Preferential Voting allows
  voters to decide their own order of preference,
  different from that indicated by the party. The
  voters may only, however, vote for one list.
  Vote-Splitting allows voters to select candidates
  from competing lists, and thus draw up their own
  list. The commonest used variation is the Closed
  List system, where the electorate are simply
  allowed to vote for one party list, not an
  individual. It is up to the party to decide who
  should get the chance to fill the seats given to
  them (usually determined well in advance with the
  candidates placed in order of priority).

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Preferential Voting

• Preferential Voting allows voters to decide their
  own order of preference, different from that
  indicated by the party.
• The voters may only, however, vote for one list.
  Vote-Splitting allows voters to select candidates
  from competing lists, and thus draw up their own
  list.
• The commonest used variation is the Closed List
  system, where the electorate are simply allowed
  to vote for one party list, not an individual. It
  is up to the party to decide who should get the
  chance to fill the seats given to them (usually
  determined well in advance with the candidates
  placed in order of priority).

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Proportional Representation

• The experience of PR has been that it has
  increased the number of women in parliaments.
  Some political parties have taken affirmative
  action and drawn up official targets for the
  proportion of women and those from ethnic
  minorities on their party lists. Defenders of
  such targets argue that although artificial, its
  aim is to temporarily speed-up change to the
  status quo, which can often only be done by such
  targets in closed PR systems.
• PR tends not to result in one party having an
  absolute majority of the votes, thus making
  coalition government the norm. This leads, in
  theory at least, to a more consensual and
  inclusive style of government.

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Mixed Systems 1

• There are a range of systems which try to strike
  a balance between majoritarian and proportional
  representation systems, and are generally (if
  rather untidily) categorised as Mixed Systems.
• These can broadly be divided into those which try
  to bring together elements of majoritarian and
  proportional systems to try and come up with a
  seat-distributing mechanism incorporating the
  best of both world (but end up tending to lean
  more towards one system or the other), and
  systems where both majoritarian and proportional
  mechanisms are used in different stages.

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Mixed Systems 2

• Cumulative or Block Vote.
• Voters have a number of votes equal to the number
  of seats available and are free to distribute
  them as they please among all the candidates,
  even to the extent that one candidate can receive
  all the votes of one voter, or conversely, where
  the voter can give each candidate one vote. Seats
  are distributed among candidates polling the most
  votes. A variation of this is Party Block Vote,
  where voters are only allowed to vote once for
  one entire party list, which results in the
  entire list of candidates of the winning party
  list taking all the seats in a multi-member
  constituency.

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Mixed Systems 3

• Limited Voting. Used in multi-member
  constituencies, voters may vote for several
  candidates on the ballot paper, but always fewer
  than the number of seats to be filled. Candidates
  polling the most votes are elected. It was used
  in some UK constituencies in the late 19th
  century.
• Single Non-Transferable Vote. Under this system,
  there are several seats to be allocated in each
  constituency. However, each voter may only vote
  for a single candidate, with those candidates who
  gain the most votes being elected.
• These systems, however, use separate majoritarian
  and proportional mechanisms for different
  constituencies
• Additional Member (or Parallel) system. A
  proportion of seats are distributed using a
  majoritarian method, while the remaining seats
  are allocated using a PR system, usually on a
  regional or nationwide basis. The Russian Duma,
  for example, has seats elected by a majority vote
  in single-member constituencies, as well as by PR
  nationally. Japan is also a user of this system.

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Mixed Systems 4

• Mixed Member Proportional system (MMP). This
  system works very similarly to Additional Member,
  in that it incorporates majority voting for one
  portion of the seats and Party List PR for the
  other. However, "under MMP the list PR seats
  compensate for any disproportionality produces by
  the majoritarian system-elected district seat
  results. For example, if one party wins 10 of
  the national votes but no district seats, then
  they would be awarded enough seats from the PR
  lists to bring their representation up to
  approximately 10 of the parliament". This
  'compensating' mechanism system is used in
  Germany, Hungary and New Zealand, and is seen as
  particularly benefitial in its ability to keep
  local constituency representation while also
  awarding smaller parties their fair share of the
  popular vote.

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Systems for National Elections in EU states 1

• The systems used for parliamentary elections in
  the member states of the European Union present a
  varied picture, each products of different
  political circumstances and traditions.
  Bicameral, unicameral, majoritarian,
  proportional, and mixed systems are all well
  represented in the EU, displaying a diversity
  which is often augmented by certain aspects of
  the electoral law not concerning the
  vote-distribution mechanisms.
• Compulsory voting rules in Belgium and Greece,
  for example, sit alongside the less demanding
  requirements of other Member States.

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Systems for National Elections in EU states 2

• In the bicameral systems, the Lower House is the
  most important, the result there determining the
  make-up of the government. A wide range of
  systems are in use for parliamentary elections,
  although proportional systems dominate. The UK
  uses the FPTP system in single-member
  constituencies. France also has single-member
  constituencies, but uses the two-stage Second
  Ballot Majority Runoff system, where an absolute
  majority is required to gain a seat. Spain, and
  Italy use the Additional Member system, while
  Germany uses the Mixed Member Proportional
  system. Finland's system is principally PR, but
  the representative for Finland is chosen by
  simple majority.

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Systems for National Elections in EU states 3

• Most of the Upper Houses are chosen by
  appointment or indirect election, while three -
  Belgium, Spain and Italy - have directly elected
  elements.
• Belgium uses the same proportionality-based
  voting system as for the Lower House, but the
  representatives are chosen along the lines of the
  regions and language communities.
• Italy uses a mixed system for the Upper House,
  most seats being filled by simple majority
  voting, the rest by proportionality.
• Spain's Upper House has most places filled by
  simple majority voting, but about a sixth of
  seats are indirectly chosen by regional
  assemblies.

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Systems for National Elections in EU states 4

• The indirectly appointed upper chambers have a
  variety of different methods for choosing
  members.
• In four of the countries - Germany, Austria,
  Holland and Spain - the Upper House is made up of
  members of regional or local assemblies. In
  France, the Senate is made up of people chosen by
  local electoral colleges.
• In Ireland, appointments to the Upper House are
  made in part by the Prime Minister and by
  indirect elections by some universities, county
  councils, panels representing different interests
  in society or the outgoing House. In the United
  Kingdom, there are four groups of members
  hereditary peers (aristocracy), life peers, Law
  lords, and certain bishops. The government
  recently started a two-stage reform of the House
  of Lords, removing the right to sit for all but
  92 hereditary peers in an "interim" house. Stage
  two will produce a final dispensation, following
  the publication of the report from a Royal
  Commission to consider the composition, roles and
  functions of the second chamber.

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Summary of voting systems 1

• Absolute Majority More than half the total
  number of votes cast. For the Absolute Majority
  system, see Second Ballot Majority Runoff.
• Additional Member (or Parallel) system Mixed
  electoral system where a proportion of seats are
  distributed using a majoritarian system, and
  where others are distributed on a proportional
  basis.
• Alternative Vote system Preferential absolute
  majority system, usually used in single-member
  constituencies, where voters number candidates in
  order of preference. If there is no outright
  winner, the least favoured candidate is
  eliminated and his second preferences are
  redistributed. This continues until someone gets
  over 50 of the vote.

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Summary of voting systems 2

• Closed List A list of candidates (in rank order
  of priority to be given seats) drawn-up for
  elections taking place by a form of Party List,
  which may not be adjusted by the voter.
• Constituency A geographical area into which a
  country is divided for elections. Can be a
  'single-member constituency' where only one
  parliamentary seat is being contested, or a
  'multi-member constituency' where more than one
  seat is being contested.

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Summary of voting systems 3

• Cumulative (or Block) Vote A majoritarian system
  for use in multi-member constituencies where
  voters have a number of votes equal to the number
  of candidates standing and are free to distribute
  them as they please. Seats are filled according
  to who receives the most votes.
• D'Hondt Quota The most common divisor used in
  the Highest Average Party PR system, it operates
  the following dividers 1, 2 , 3, 4, etc.
• Droop Quota Used for allocating seats in both
  the Greatest Remainder Party List and the Single
  Tranferable Vote systems, it

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Summary of voting systems 4

• Elimination In Alternative Vote and STV systems,
  it occurs when candidates have too few votes to
  remain in a contest.
• 'First-Past-The-Post' (FTPT)(or Simple majority)
  system Candidate with the largest number of
  votes wins, regardless of whether he or she has
  an absolute majority.
• Greatest (or Largest) Remainder system A Party
  List PR system which uses a type of formula (e.g.
  Hare, Imperiali, etc) to devise a quota of the
  votes necessary for a party to secure a seat.
  Once all seats have been distributed according to
  the quota, remaining votes which do not reach the
  quota are counted to distribute any remaining
  seats to those with the most votes left-over.

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Summary of voting systems 5

• Hare (or Simple) Quota A variety of the Greatest
  Remainder Party List PR system, it is a quota
  calculated as 'votes divided by seats'.
• Highest Average system A Party List PR system
  which distributes seats according to parties
  which have the highest averages after being
  divided by a particular formula (e.g. d'Hondt,
  Sainte-Lague system, etc).
• Imperiali Quota The quota under this system is
  reached by dividing the total number of votes
  cast by the number of seats to be filled,
  increased by two.
• Limited Vote Used in multi-member
  constituencies, voters may vote for several
  candidates on the ballot paper, but always fewer
  than the number of seats to be filled. Candidates
  polling the most votes are elected.

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Summary of voting systems 6

• Majoritarian systems Generic term for systems
  where seat(s) are distributed according to
  whichever candidate(s) get the most individual
  votes.
• Mixed Member Proportional system (MMP) This
  system works very similarly to Additional Member,
  in that it incorporates majority voting for one
  portion of the seats and Party List PR for the
  other. However, it differs in its ability to
  award seats through PR to over-compensate for
  parties which attracted a good share of the
  popular vote in the majoritarian elections, but
  failed to make any gains.
• Mixed systems Generic term for single electoral
  systems which are either composed of elements of
  both majoritarian and proportional systems or
  those which include separate majoritarian/proporti
  onal procedures, such as the Additional Member
  system.
• Parallel system See Additional Member system.

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Summary of voting systems 7

• Party Block Vote Voters are only allowed to vote
  once for one entire party list, resulting in the
  entire list of candidates of the winning party
  list taking all the seats in a multi-member
  constituency.
• Party List system The principal PR system,
  operated by either Greatest Remainder or Highest
  Average formula, it is an election in a
  multi-member constituency where all candidates
  are placed on political party 'lists'. Depending
  on the variety, an electorate may only be able to
  vote according to Closed List rules, may be able
  to partake in Preferential Voting, or could even
  pick and choose candidates from across the lists,
  as allowed by Vote-Splitting.

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Summary of voting systems 8

• Preferential Voting Party List PR rule variant
  which enables voters, once they have voted for
  one party list, to choose their prefered ranking
  of candidates.
• Proportional Representation (PR) Generic term
  for systems which seek to ensure that the results
  of elections are as proportional as possible to
  the make-up of an electorate. Party List systems
  and STV are varieties of PR.

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Summary of voting systems 9

• Quorum a minimum level - usually a percentage -
  of the full electorate required to vote to
  validate the results of an election. (i.e. If
  only 29 of an electorate voted in an election
  requiring a 35 quorum, the results would be
  deemed invalid due to the low level of voter
  participation).
• Single Non-Transferable Vote A mixed system for
  use in multi-member constituencies, where voters
  only have one vote. Those who receive the most
  votes win.
• Single Transferable Vote (STV) Main alternative
  PR system to Party List, a candidate is elected
  as soon as he reaches the a quota calculated by
  the Droop quota. Additional votes are
  redistributed to other candidates on the basis of
  second choices. The same operation is carried out
  in the case of the candidate who polled fewest
  votes, who is eliminated. If there are still
  seats to be filled after the second count, the
  process continues.
• Threshold A minimum condition for securing
  representation. This divide limits purely
  proportional results by distributing seats only
  to parties with
• Vote-Splitting This allows voters to select
  candidates from competing lists in a Party List
  PR system, and thus draw up their own list of
  candidates.
•  

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Conclusions

• There is no perfect voting system (but we knew
  that from Arrow!).
• There is a big literature pointing out the pros
  and cons of the various systems.
• Different countries have different systems.
• Why?
• Partly historical and partly cultural.