Hard Choices in Deliberative Democracy

1
Hard Choices in Deliberative Democracy

• David Gray
• Department of PhilosophyCarnegie Mellon
  University

2
Overview

• Deliberative Democracy
• The Social Choice Critique
• Arrows Theorem
• A Standard Response
• Relax Universal Domain
• A Better Response
• Reject Pair-Wise Comparisons
• Embrace Interpersonal Cardinal Utilities
• A New Model of Rational Decision Making

3
Tools for E-Democracy at Carnegie Mellon
University
4
Deliberative Democracy

• Citizens deliberate over those social policies
  and laws affecting them

5
Deliberative Democracy

• When deliberation ends a choice must be made for
  what policy or law should be adopted

6
Deliberative Democracy

• This involves aggregation

7
The Social Choice Critique

• There are serious challenges for aggregation
• Aggregation mechanisms, such as voting, are
  inherently flawed
• No legitimate aggregation method
• Only hope vote the bastards out
• Our tools must be able to deal with these
  challenges

8
Arrows Theorem

• No aggregation mechanism can satisfy
• Completeness and Transitivity
• Universal Domain (U)
• Weak Pareto Principle (P)
• Independence of Irrelevant Alternatives (I)
• Non-Dictatorship (D)

9
The Deliberative Democratic Response

• Deliberation contests some of Arrows assumptions
• For instance, (U) is denied
• Claro! vs. Public Reasons
• Certain rankings are not permitted, because in
  deliberation participants
• Identify relevant attributes
• Prioritize them
• The individual preference orderings are shaped
  accordingly

10
The Deliberative Democratic Response

• If participants come with rankings that are
  multi-peaked

1st
2nd
3rd
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The Deliberative Democratic Response

• Deliberation may cause their preferences to
  become single-peaked

1st
2nd
3rd
12
The Deliberative Democratic Response

• Duncan Blacks Result There will be a pair-wise
  majority winner and a social ordering

1st
Ordering y z x
2nd
3rd
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Evaluation of this Response

• Strength
• Facilitates multi-attribute decision making
• Weaknesses
• Too Ambitious
• Will orderings always become single-peaked?
• Will participants become clearer about their
  preferences?
• Too Weak
• Could orderings become multi-peaked?
• Could participants become more confused?
• It is not sufficient

14
The Need to Change Assumptions

• The denial of (U) is dubious
• Other options are available
• Relax deeper assumptions
• Pair-Wise Comparisons
• Non-Interpersonal Cardinal Utilities

15
Arrows Theorem

• Completeness and Transitivity
• Pair-Wise Comparisons
• Universal Domain (U)
• Pair-Wise Comparisons
• Independence of Irrelevant Alternatives (I)
• Pair-Wise Comparisons
• Non-Interpersonal Cardinal Utilities

16
The Need to Change Assumptions

• Do not have to hope that deliberation changes
  preferences and in a good way to relax (U)
• Instead, assume that deliberators might already
  have a rich appraisal of their options, which
  relaxes (U)

17
A Paradoxical Individual

• An American fiscal conservative, hawk
• Three options for rebuilding post-war Iraq
• A UN led initiative
• A NATO led initiative
• Setting up a USA controlled Puppet Regime

18
A Paradoxical Individual

• Get the following a pair-wise choices
• UN over NATO
• NATO over Puppet Regime
• Puppet Regime over the UN
• Yet given the three options, he chooses the UN
  option

19
A Paradoxical Individual

• How is this possible?
• Is he hopelessly irrational?
• What is in the options that pair-wise comparisons
  are missing?

20
Conflicting Presidential Orders

• A fiscal conservative, hawk
• Considering three options
• UN led initiative
• USA led initiative
• NATO led initiative

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Conflicting Presidential Orders

• A fiscal conservative, hawk
• Considering three options
• UN led initiative
• USA led initiative
• NATO led initiative

22
Conflicting Presidential Orders

• A fiscal conservative, hawk
• Considering three options
• UN led initiative
• USA led initiative
• NATO led initiative

23
Conflicting Presidential Orders
24
Conflicting Presidential Orders

• Chooses the NATO option
• Argues it is the 2nd Best option available

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Conflicting Presidential Orders

• NATO will not participate
• Presented with another option
• On pair-wise comparisons, it ranks the same as
  NATO
• Setting up a USA backed Puppet Regime

26
Conflicting Presidential Orders
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Conflicting Presidential Orders

• Chooses the USA option
• Argues that the Puppet Regime was the 2nd Worse
  option available

28
Conflicting Presidential Orders

• Chooses NATO

• Chooses USA option

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Conflicting Presidential Orders
NATO!Or USA? Bed time?

• How is this possible?
• If he first picks NATO option then he ought to
  Puppet Regime option
• Is he hopelessly irrational?
• What are the pair-wise comparisons missing?

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What is to be done?

• What if these people are perfectly rational?
• Pair-wise comparisons seem to be missing out on
  vital information
• Dethrone pair-wise comparisons!

31
An Alternative Model for Rational Decision Making

• Rational decision making when values conflict
  over an option and the values themselves cannot
  resolve the conflict
• Reject pair-wise comparisons
• Adopt cardinal rankings
• Allow interpersonal cardinal utilities

32
Understanding the President

• Two of his key values are in conflict over the
  issue of how to rebuild Iraq
• Fiscal Conservative Expenses for the US
• Hawk Expansion of US control

33
Understanding the President

• Examining how his values rank the options
• Expenses
• UN Led 150 Million
• NATO Led 405 Million
• USA Led 1 Billion
• Control
• USA Led 100 Effective
• NATO Led 77.5 Effective
• UN Led 25 Effective

34
Understanding the President

• We set each value as an axis, and place each
  option on these depending on their relative
  desirability

USA Led
UN Led
100
100
NATO Led
NATO Led
70
70
USA Led
UN Led
0
0
USA Control
USA Expenses
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Understanding the President

• We then take the weighted average of each option
  over these values

UN Led
NATO Led
USA Led
USA Control
USA Expenses
36
Understanding the President

• Those options which form the dominating upper
  bound over these values are then admissible under
  these values

UN Led
NATO Led
USA Led
USA Control
USA Expenses
37
Understanding the President

• Second-order values can then break any ties
  created by the first order values

UN Led
NATO Led
USA Led
USA Control
USA Expenses
38
Understanding the President

• Second-order values can then break any ties
  created by the first order values

NATO LedUSA Led UN Led
UN Led
NATO Led
USA Led
USA Control
USA Expenses
39
Understanding the President

• When the NATO option is no longer available, the
  option of setting up a Puppet Regime is under
  consideration

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Understanding the President

• Examining how his values order the options
• Expenses
• UN Led 150 Million
• Puppet Regime 745 Million
• USA Led 1 Billion
• Control
• USA Led 100 Effective
• Puppet Regime 47.5Effective
• UN Led 25 Effective

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Understanding the President

• The Puppet Regime option is NOT admissible under
  these values

UN Led
Puppet Regime
USA Led
USA Control
USA Expenses
42
Understanding the President

• So USA option is preferred

Puppet RegimeUSA Led UN Led
UN Led
Puppet Regime
USA Led
USA Control
USA Expenses
43
Second Best and Second Worst Options

• Distinguish between second-best and second-worst

UN Led
UN Led
NATO Led
VS.
Puppet Regime
USA Led
USA Led
USA Expenses
USA Control
USA Control
USA Expenses
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Understanding Cycles

• Pair-wise comparisons yield a cycle
• Favors UN over NATO
• Favors NATO over Puppet Regime
• Yet, favors a Puppet Regime over the UN
• When faced with all three options, chooses UN

45
Understanding Cycles

• When faced with all three options

UN Led
NATO Led
Puppet Regime
USA Control
USA Expenses
46
Understanding Cycles

• When faced with all three options

Puppet RegimeUN Led NATO Led
UN Led
NATO Led
Puppet Regime
USA Control
USA Expenses
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Understanding Cycles

• UN vs. NATO UN wins

UN Led
NATO Led
USA Control
USA Expenses
48
Understanding Cycles

• UN vs. NATO UN wins

Puppet RegimeUN Led NATO Led
UN Led
NATO Led
USA Control
USA Expenses
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Understanding Cycles

• NATO vs. Puppet Regime - NATO wins

NATO Led
Puppet Regime
USA Control
USA Expenses
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Understanding Cycles

• Yet, Puppet Regime vs. UN Puppet Regime Wins

UN Led
Puppet Regime
USA Control
USA Expenses
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Understanding Cycles

• Yet, Puppet Regime vs. UN Puppet Regime Wins

Puppet RegimeUN Led NATO Led
UN Led
Puppet Regime
USA Control
USA Expenses
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Alternative Foundation for Rational Choice
Making

• Devalue pair-wise comparisons
• Use cardinal rankings with a lexicographic method
• Allows to
• Distinguish between second-best and second-worst
• Rationalize some cycles

53
Social Choice Making

• Each individual has cardinal ranking(s)

USA Led
UN Led
100
100
NATO Led
NATO Led
70
70
Puppet Regime
30
30
Puppet Regime
Hawk
Fiscal Conservative
USA Led
UN Led
0
0
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Social Choice Making

• which are interpersonally comparable

UN Led
100
NATO Led
70
USA Led
50
NATO Led
35
30
Puppet Regime
Puppet Regime
15
Hawk
Fiscal Conservative
USA Led
0
UN Led
0
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Social Choice Making

• and begin to eliminate options
• Many ways to do this!!

UN Led
NATO Led
Puppet Regime
USA Led
Hawk
Fiscal Conservative
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The Role for Deliberation

• Reveals the dimensions to the issue
• Allows participants to communicate effectively
  with one another
• Supplies cardinal values to their preferences
• Makes possible for determining interpersonally
  comparable interests
• Allows participants to become aware of trade-offs
  between aggregation mechanisms involving
  interpersonal comparisons
• Facilitate agreement on a procedure for combining
  interpersonally comparable interests into a
  social choice

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Conclusions

• Pair-wise comparisons screen off valuable
  information
• Prevents us from seeing certain admissible and
  inadmissible options (second best and second
  worst options)
• Cannot comprehend how some cycles might be
  rational
• With pair-wise comparisons we can never know if
  participants preferences have a richer, more
  subtle structure

58
Conclusions

• Deliberative democrats have to go further if they
  wish to respond to their social choice critics
• They only challenge the surface assumptions in
  social choice
• There are alternative ways to defend deliberative
  democracy from its social choice critics
• Challenge deeper assumptions in social choice
  theory