Chapter 4
Chapter 4: Vocabulary & Core Definitions
Strategy:
Definition: An action that a person may choose while being aware of the mutual dependence of their outcomes on both their and others' actions.
Social Dilemma:
Definition: A situation in which actions taken independently by self-interested individuals lead to a socially inferior outcome compared to the outcome achievable through cooperation.
Example: Climate change and antibiotic resistance are classic examples where individual actions can lead to detrimental collective outcomes.
Free Rider:
Definition: An individual who benefits from the contributions of others in a cooperative project while contributing nothing themselves.
Game Theory:
Definition: A branch of mathematics that models strategic interactions; situations where outcomes for each individual depend on the actions of all involved parties.
Best Response:
Definition: The strategy that provides the highest payoff for a player, given the strategies chosen by other players.
Nash Equilibrium:
Definition: A set of strategies, one for each player, in which every player is playing their best response to the strategies chosen by others.
Key feature: No player has an incentive to unilaterally change their action, as doing so would not improve their payoff.
Dominant Strategy:
Definition: A strategy that yields the highest payoff for a player, independent of the actions of other players.
Dominant Strategy Equilibrium:
Definition: An outcome where all players are playing a dominant strategy.
Prisoners’ Dilemma:
Definition: A game scenario characterized by a dominant strategy equilibrium that is not Pareto efficient; individual self-interest leads to a suboptimal outcome for all players.
Altruism:
Definition: A social preference where an individual is willing to incur a cost in order to benefit another person.
Chapter 4: Additional Concepts
Reciprocity:
Definition: A preference to reciprocate kindness toward those who act kindly and to punish those who violate social norms.
Social Norm:
Definition: A shared understanding common to most members of a society regarding acceptable behavior.
Example: Norms regarding fairness in social interactions.
Public Good Game:
Definition: A game in which individuals decide how much to contribute to a shared resource pool.
Outcome: Typically results in free-riding when played once by self-interested agents, yet sustained cooperation can occur through social norms or punitive measures.
Ultimatum Game:
Definition: A sequential game where one player (the Proposer) offers a division of a sum of money to another player (the Responder), who can either accept the offer (resulting in the proposed distribution) or reject it (resulting in no payment to either).
Purpose: A tool to study preferences for fairness.
Prediction: Homo economicus (self-interested individuals) would propose minimal amounts, while Responders would accept these offers.
Reality: Responders often reject low offers as a form of punishing unfairness, while Proposers usually offer between 40%-50% of the sum to avoid rejection.
Crowding Out:
Definition: A phenomenon where economic incentives (e.g., fines or prices) displace ethical or social motivations.
Example: In a case study where a fine for lateness was introduced at a daycare, parents became even more late, indicating that the monetary fine altered their perception of moral obligation.
Pareto Efficiency:
Definition: A situation is Pareto efficient if no one can be made better off without making someone else worse off.
Context: An allocation is considered efficient when there are no alternative allocations that could benefit at least one individual without harming others.
Coordination Game:
Definition: A game characterized by multiple Nash equilibria where players typically prefer to coordinate on the same actions, or ones that are compatible.
Example: Deciding which side of the road to drive on, where effective coordination leads to reduced accidents.
Chapter 4: Key Concepts & Models
A. Types of Games
Invisible Hand Game:
Definition: A game where independent pursuit of self-interest leads to a Pareto-efficient outcome.
Example: The scenario involving Anil and Bala, where they grow crops best suited to each, leading to maximized payoffs for both.
Prisoners’ Dilemma:
Definition: In this game, the dominant strategy is to defect, leading to an outcome of (Defect, Defect) which is Pareto-dominated by mutual cooperation (Cooperate, Cooperate).
Solution: Sustained cooperation can be achieved through social preferences such as altruism, repeated interactions, or institutional mechanisms like fines and regulations.
Public Good Game:
Definition: Considered as a multi-player prisoners' dilemma where the dominant strategy is to contribute nothing, hence leading to free-riding.
Ultimatum Game:
Utilized primarily to study fairness and bargaining behavior.
Predictions and realities show a gap between self-interested behavior and actual decision-making, as discussed above.
Coordination Games:
Description of potential conflicts of interest illustrated by situations like the Battle of the Sexes or the Hawk-Dove game, particularly in modeling climate change negotiations.
Here, both players aim to avoid the worst outcomes while preferring different equilibrium strategies.
B. Evaluating Outcomes
Pareto Criterion:
Allocation A is said to dominate allocation B if at least one individual is better off in A with no one worse off.
Definition: The result of an economic interaction is characterized as an allocation, where Pareto efficiency occurs if no alternative allocation can make at least one individual better off with none worse off.
Limitations: Pareto efficiency does not inherently imply fairness; a scenario where one individual possesses all the resources may still be Pareto efficient. Additionally, multiple Pareto-efficient outcomes are possible.
C. The Tragedy of the Commons
Concept Introduction:
Proposed by Garrett Hardin, this concept highlights how resources that lack ownership (open-access resources) are prone to overexploitation.
Elinor Ostrom's Rebuttal:
Ostrom, a Nobel Prize-winning economist, argued that local communities can manage common-pool resources effectively without the need for top-down government regulation.
This management relies on informal rules, social norms, and peer punishment to convert open-access resources into common property.
Chapter 4: Key Examples
A. Anil and Bala (Crop Choice)
Invisible Hand Game:
Scenario where Anil specializing in growing Cassava and Bala growing Rice results in maximized individual and collective payoffs.
B. Anil and Bala (Pest Control)
Prisoners' Dilemma:
Decision-making scenario between environmentally friendly Integrated Pest Control (IPC) and the cheaper but harmful Toxic Tide.
Outcome: Both players opt for Toxic Tide, a dominant strategy, leading to environmental degradation and a worse outcome than had they both cooperated using IPC.
C. The Irrigation Project
Public Good Game:
Farmers face a decision to contribute to the maintenance of irrigation.
Result of self-interested behavior leads to no contributions and the failure of the project if everyone acts selfishly.
D. The Israeli Day Care Experiment
Crowding Out Effect:
Introduction of a fine for parents who arrive late paradoxically results in an even higher rate of lateness.
Explanation: The fine recontextualizes lateness as a service that can be bought rather than a moral obligation, thus crowding out the ethical motivation for punctuality.
E. Climate Change Negotiations
Modelled as Hawk-Dove Game:
Involving major players like China and the US, where both prefer to maintain a business-as-usual (BAU) approach while the other restricts emissions.
Consequence: Potential catastrophic outcomes arise from mutual pursuit of self-interest, leading to a stagnant conflict regarding emission restrictions.
Chapter 4: Important Figures
John Nash:
Notable for developing the concept of Nash Equilibrium, showcasing its existence across various classes of games.
Elinor Ostrom:
Recognized as a Nobel Prize laureate for her work indicating that local communities can manage common-pool resources effectively through self-governance and social norms, which challenged perceptions of the necessity of external regulation.
Vilfredo Pareto:
An economist famed for his work on the Pareto criterion and for his observation related to wealth distribution, notably referred to as Pareto's Law or the 80-20 rule.