Unidimensional spatial model

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Unidimensional spatial model

• Stewart, Chapter 1

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Plan of presentation

• Why do we care about theory or explanation at
  all?
• History of studying Congress
• Politics of Lineland

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I.Why do we care about theory or explanation at
all?

• Thats what social scientists do
• Thats what politicians do
• Thats what citizens do
• Think about the current campaign and ideological
  polarization

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Different professions have different ways of
theorizing about legislatures

• Activists good guys and bad guys
• Reporters individual stories about good guys
  and bad guys
• Political scientists The general, generic, and
  predictable

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II.Brief history of political science

• Early days 1880 formalism
• 1900 to 1950 Progressivism
• 1950-1980 Sociology
• 1980 to present Economics

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What are they?

• Formalism understand Congress by the written
  rules.
• Progressivism understand Congress by comparing
  to normative standards
• Sociology
• The group is what is important
• Congress is a group, made up of other groups
• Economics
• The individual is what is important
• Collective behavior derives from individual
  interests, preferences, and behaviors

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Congress and intelligence reform

• Formalist
• What does the Constitution say about the role of
  Congress and the Executive in intelligence?
• Progressive
• Does the Constitution actually govern the
  exercise of intelligence?
• Is intelligence gathering a war making power?
• Sociology
• Who are the actors? What (social) roles do they
  play?
• What factors constrain the actors to stay within
  their roles (e.g. what is the committee
  environment)?
• Economics
• Who are the relevant actors, what are their goals
  (election, power, policy)
• What are the strategic moves that the individuals
  make in order to optimize over the policy space?

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Advancements in legislative studies

• Our understanding of legislatures has become more
  precise over time
• Modern legislative analysis focuses on the
  interaction between individuals and institutions
• Without institutions, decision making is chaotic
• Heritability problem
• Theoretical primitives
• Preferences
• Rules

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Logic of this style of analysis

• Begin with simple preferences
• How does decisionmakingproceed without
  institutions?
• How does decisionmakingproceed withinstitution?
• Add complexity and stir

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The politics of lineland

• Think of the world as a single dimensional policy
  space
• Harold Hotellings grocery store problem
• Downsian model of competition converge on the
  median voter
• No matter the shape of the underlying
  distribution!

C1
C2
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More formally

• We care about
• Preferences
• Alternatives
• Rules

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Preferences

• Dimensionality (1,2,many)
• Location and characteristics of preferences
• Ideal points
• Utility curves

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Different curves
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Alternatives

• Plain English motions, amendments, etc.
• Expressed in same coordinate system as
  preferences
• Heresthetics (Riker) The art/science of trying
  to alter the dimensionality of a policy debate
• Clinton impeachment (private sex vs. perjury)
• 9/11-related detainees (civil liberties vs.
  security)
• Framing of Bush/Kerry campaign

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Framing in Bush/Kerry Campaign
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The importance of the reversion point or status
quo

• The point where we end up if nothing happens. It
  is an outcome.
• The most important alternative
• Taxing vs. spending may have different reversion
  points
• E.g. Public schools in Pacific N.W.

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Rules Matter

• Majority requirement
• Simple or supermajority?
• Agenda setting
• Which alternatives and in which order?
• Pure majority rule does it ever happen?
• Example Oleszek pg. 231 (6th edition)

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The median voter theorem drives this analysis

• IF
• The issue is unidimensional
• Voters decide based on their preferences
• Preferences are single-peaked
• Voting proceeds under pure majority rule
• THEN
• The median voters ideal point will prevail
• Or the median is the dictator

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Reminders symmetry does not matter, only single
peakedness
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Example of a lack of a single peak
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The politics of flat land
PA(SQ)
PB(SQ)
A
SQ
B
C
Pc(SQ)
Ic(SQ)
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Who was the median voter in Congress in 2003?