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3.3: Voting III: Democracy2?

ECON 410 · Public Economics · Spring 2020

Ryan Safner
Assistant Professor of Economics
safner@hood.edu
ryansafner/metricsf19
publicS20.classes.ryansafner.com

The Story So Far

  • Pure democracy (majority rule) is indeterminate
    • Condorcet's Paradox: cycling from 3+ choices, 3+ voters, and disagreement
    • Arrow's Impossibility Theorem: no non-dictatorial rule can efficiently and fairly determine a group choice
    • Agenda control & strategic voting

The Story So Far

  • Democracy devolves into dictatorship or institutions are created to restrict choice
    • Constitutional republics: limit domain of what may be voted on
    • Real world electoral systems reduce effective choices to 2
    • First-Past-The-Post: Duverger's Law two political parties
    • Parliamentary: "government" vs. "opposition"

The Story So Far

  • Voters imperfectly vote for a candidate closest to their preferences

  • Voters have poor incentives (MC>MB) to inform themselves or to vote for the best candidate

    • Good governance is a public good with free rider problem
    • Rational ignorance
    • Rational irrationality

Radical Markets

Eric Posner

Glen Weyl

2018, Radical Markets: Uprooting Capitalism and Democracy for a Just Society

  • A series of proposals to make markets and democracy more free and efficient, but also more equal and just

    • too much inequality and market power right now
  • Argued economically, often market-like proposals

    • mechanism design, game theory

What's Wrong With 1P1V?

  • The bedrock of democracy is the idea of One person, one vote (1p1v)

    • Everyone has equal voice in the outcome
  • Used to argue for extending the franchise to women, African Americans, etc

  • Constitution requires representation in Congress apportioned to population

What's Wrong With 1P1V?

  • Tyranny of the majority: unprotected minorities can get trampled on by the majority

  • Persistent minorities view system as illegitimate, turn to other means of resistance

    • secession, riots, violence

What's Wrong With 1P1V?

  • U.S. only started protecting a lot of abused minorities in 20th century

  • Mostly result of federal court cases

    • Not very democratic! Unelected, unaccountable life-long judges
    • Seem to rely on preferences of judges

Federal troops protecting the "Little Rock Nine" during racial integration of schools.

What's Wrong With 1P1V: Ordinality

  • Voting systems give equal weight to preferences by person

  • No way to differentiate preferences or intensities

    • Only ordinal rankings: A>B or A<B
  • An indifferent, lethargic majority, can outvote a passionate minority

Cardinality: In Markets

  • In markets, not only more choices, but can indulge intensity of your preferences

  • If you want 4 more cookies, you can buy 4 more cookies

  • Goods flow to those that value them the most, willing to pay the most

From Markets to Politics

  • But we can't easily transfer market mechanisms to collective choices

  • Free rider problem of voting and informing oneself

  • Voters with the strongest preferences can just try to "buy" the most votes

From Markets to Politics

  • Olson: smaller, more passionate groups can better organize than large, apathetic groups

    • most people don't know (or care) about bank regulation, nuclear power, emissions standards
    • rational ignorance
  • Special interest groups have a strong incentive to capture the democratic process

    • rational: high level of participation

Getting the Price Right

  • In markets, the cost of acquiring more goods is proportional to how much you want them
    • Again, for 4 more cookies, pay 4x the price of one

Getting the Price Right

William Vickrey

1914-1996

Economics Nobel 1996

  • Work on auctions and auction theory

  • Auction's goal: get item to the person who values it the most

Getting the Price Right

William Vickrey

1914-1996

Economics Nobel 1996

  • Turns out, more important to get the winner to pay the price that compensates for the cost that they create

    • Other bidder cannot get the item
  • Vickrey or Second-price auction: Winner pays the bid of the second-highest bidder

  • Markets, in general: prices reflect opportunity cost of next best alternative use

    • What somebody else is willing to pay for a different use

Getting the "Voting Price" Right: A Hypothetical for Intuition

  • Suppose society votes to zone land for cattle ranching, optimum at A

Getting the "Voting Price" Right: A Hypothetical for Intuition

  • Suppose society votes to zone land for cattle ranching, optimum at A

  • But more ranching imposes a cost on Farmer Frank (Cows eat his crops)

  • Without Frank, optimal ranching is at A.

  • But with him, social cost increases, moving social optimum back to B.

Getting the "Voting Price" Right: A Hypothetical for Intuition

  • In some sense, Frank imposes an externality on society for reducing its ranching from A to B

  • Frank should have to "pay" for the additional external cost imposed, which is the area of the DWL triangle

Getting the "Voting Price" Right: A Hypothetical for Intuition

  • What if the cost to Frank is actually larger?

  • Area of DWL triangle grows in size with the square of the reduction in quantity

  • More valuable land (higher MSB) is prevented from becoming farmland

    • Value of lost farmland is increasing as more farmland is being lost!

From Prices to Votes

  • But this ruling is going to be determined by votes, not market prices or transactions

  • Under 1p1v, marginal cost of "buying" votes is constant

  • Those that care very much try to buy all the votes

    • Cost per vote to them is too low
  • Those that don't care very much

    • Cost per vote to them is too high

From Prices to Votes

  • Posner & Weyl's proposal: "Quadratic Voting"
  1. What if people could "buy" votes to spend on an issue

  2. The total cost of buying votes should increase quadratically

    • i.e. cost of n votes is n2; or
    • most votes you could buy with x is x

Quadratic Cost Structure

Votes Total Cost Marginal Cost
1 1 -
2 4 3
3 9 5
4 16 7
5 25 9
6 36 11
7 49 13
8 64 15
9 81 17
10 100 19
  • Unlike 1p1v, Marginal cost of additional vote increases proportionate to the number of votes cast

Proposed Benefits of Quadratic Voting

  • Get a better indication of people's preferences

  • Reduces strategic voting, cycling, free-rider problem

  • More of an incentive to inform oneself - have one's votes count proportionate to degree of interest

  • A passionate minority can now outvote an indifferent majority

    • Is that what we want??

How Might it Work?

  • Imagine each person is given a budget of "voice credits" Q per year (e.g. 100 Q)

  • For each issue, individual can expend x Q-credits to cast x votes

  • Q-credits "rollover" if not spent on issues

  • Can save credits for issues you care more about

How Might it Work?

  • Each person can cast as many votes as desired FOR and AGAINST any proposal

  • If total votes For > total votes Against, resolution passes (and vice versa)

How Might it Work?

  • Multiple option voting:
    • Have a default option
    • People can cast as many votes FOR and AGAINST as many options as they want
    • If any option gets the most votes, enacted
    • If no option gets most votes, default option enacted

Interest in Quadratic Voting Beyond Politics

The Story So Far

  • Pure democracy (majority rule) is indeterminate
    • Condorcet's Paradox: cycling from 3+ choices, 3+ voters, and disagreement
    • Arrow's Impossibility Theorem: no non-dictatorial rule can efficiently and fairly determine a group choice
    • Agenda control & strategic voting

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