POLS1008 Lecture Notes - Lecture 3: Literacy Test, Subgame Perfect Equilibrium, Non-Cooperative Game Theory
L3 THE ETHICS OF RATIONALITY OF VOTING
Instrumental rationality and voting
pB > C
Probability you are decisive x Benefit of getting your preferred policy > Cost associated with voting
What’s the problem?
Probability you are decisive is extraordinary small…
- P = 0.0000001 (Gelman)
- P = 0.00000006 (McLean)
- P = 10*90 (Carling)
What we know: at the margins
- We know that increasing C leads to lower voter turnout and increasing B or p resulting in higher
voter turnout
- Lower turnout where:
oBad weather
oLegal barriers (poll tax, literacy test)
oExpensive registration
oFew polling stations
oJury service lists
- Higher turnout where:
oSignificant items on the ballot (budget)
oSmaller electorate
oCloser election
Potential solutions to the ‘paradox’
- Negligible voting cost? (Yet marginal effects)
- Information costs
oIs it worth it to be informed?
oRational ignorance
- Overestimation of p
find more resources at oneclass.com
find more resources at oneclass.com
oAllow p to evolved over time:
If it is common knowledge that the probability of decisiveness is infinitesimal, no one
has incentive to vote, and therefore few vote!
Now the change of casting a decisive vote is very high! All of a sudden it is rational to
vote again!
At equilibrium, high voter turnout! (assumes complete information about
preferences and voting costs of others)
- Evidential decision theory:
oAct on the basis of statistical correlations, not causal links
oE.g. smoking does not in fact cause cancers (lets assume) but instead is just strongly
correlated with cancer
oThere is a statistical relationship between people like me voting for candidate A, and the no.
of votes A receives. Yet my vote will not cause people like me to vote for A!
Instrumental rationality and voting
pB + D > C
- D captures the satisfaction derived from..
oFulfilling a civic duty
oAffirming allegiance to the political system
oExpressing a preference
oA whole slew of other private motivations
Instrumental versus expressive value
Instrumental value: ‘what a product does’. Geoff Brennan
- Consumers also care about the expressive value of products. What they indicate or ‘say’ about a
person!
- Most products have a mix of instrumental and expressive value
- Voting has both kinds of value!
- How to compare instrumental to expressive value?
oSince probability of being decisive is too small, expressive value overrides the instrumental
value!
oIn other words, while your vote is not going to likely change the outcome of the election,
you get the expressive value of your vote regardless!
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Probability you are decisive x benefit of getting your preferred policy > cost associated with voting. C leads to lower voter turnout and increasing b or p resulting in higher voter turnout. Lower turnout where: bad weather, legal barriers (poll tax, literacy test, expensive registration, few polling stations, jury service lists. Higher turnout where: significant items on the ballot (budget, smaller electorate, closer election. Information costs: is it worth it to be informed, rational ignorance. Overestimation of p: allow p to evolved over time: If it is common knowledge that the probability of decisiveness is infinitesimal, no one has incentive to vote, and therefore few vote! Now the change of casting a decisive vote is very high! All of a sudden it is rational to vote again! At equilibrium, high voter turnout! (assumes complete information about preferences and voting costs of others) Yet my vote will not cause people like me to vote for a!
