Study Notes on Bounded Rationality by Gerd Gigerenzer

Bounded Rationality: An Overview

Author: Gerd Gigerenzer
DOI: 10.4324/9781315658353-2

Introduction to Bounded Rationality

  • Definition: Bounded rationality is a concept that refers to the limitations of human decision-making processes.

  • Three Faces:

    • Herbert A. Simon's Original Definition: The term was coined by Herbert A. Simon, representing the limitations in human reasoning when faced with uncertainties that deviate from the ideal conditions of ration.

    • Contradictory Interpretations: Two later interpretations of bounded rationality took on meanings that conflicted and absorbed the term differently.

  • Significance: These different interpretations reflect distinct research agendas and perceptions of human rationality.

Simon's Original Concept of Bounded Rationality

  • Background:

    • Herbert A. Simon (1916–2001) first encountered bounded rationality while working in the Milwaukee recreation department.

    • He found that budget decision-making did not align with utility maximization principles.

  • Key Realization: Managers used rough decision-making rules rather than meticulous comparisons of marginal utility and costs, leading Simon to conclude that traditional economic models fail to describe real human decision-making accurately.

  • Research Question: Simon posed the question: "How do human beings reason when the conditions for rationality postulated by neoclassical economics are not satisfied?"

Traditional Neoclassical Rationality

  • Three Pillars of Rationality:

    1. Consistency: The choices made by individuals should be consistent over time.

    2. Maximization of Expected Utility: Individuals aim to maximize their expected outcomes based on the probabilities of various potential results.

    3. Bayesian Updating: This involves adjusting probabilities as new information becomes available.

Characteristics of a "Small World" = what is rationality

  • Definition: A small world is characterized by:

    1. Perfect Foresight of Future States (S): Comprehension of exhaustive and exclusive potential future states.

    2. Perfect Foresight of Consequences (C): Understanding of all possible outcomes attached to each action taken in a particular state.

  • Examples of Small Worlds:

    • Lotteries with known probabilities.

    • Games like roulette where all potential outcomes are known.

Distinction Between Risk and Uncertainty

  • Risk:

    • Situations with perfect foresight and known probabilities of outcomes.

  • Uncertainty:

    • Situations where either the future states or their probabilities are not known, comprising ambiguous and fundamentally uncertain scenarios.

  • Implication: Most real decision-making problems humans face occur under conditions of uncertainty, not risk.

Principles of Simon's Bounded Rationality Program

1. Uncertainty

  • Study decisions made under uncertainty rather than solely under risk.

2. Process

  • Investigate actual decision-making processes instead of merely using as-if models based on expected utility maximization.

3. Scissors Analogy

  • Behavior is a function of the interaction between cognitive capabilities and environmental structure (the scissors analogy).

Critiques and Misinterpretations of Bounded Rationality

  • During Simon's lifetime, economists largely ignored his research questions and preferred models based on perfect foresight.

  • Friedman's As-If Defense: Milton Friedman posited that economic models need only predict outcomes effectively and not necessarily reflect real human decision-making processes.

The Three Conflicting Interpretations of Bounded Rationality

1. Homo Heuristicus

  • Represents Simon's original concept emphasizing decision-making under uncertainty.

2. Homo Economicus

  • Represents the neoclassical notion of decisions made under risk, adhering to expected utility maximization principles.

3. Homer Simpson

  • A satirical name for the heuristics-and-biases framework that attributes deviations from rationality to inherent flaws in human behavior rather than theoretical flaws in decision-making models.

Tools for Decision-Making Under Uncertainty

  • Heuristics: it’s a short cut or a rule of thumb

    • Tools like satisficing which aim for a satisfactory rather than optimum solution based on available information.

  • Aspiration Levels: Setting a benchmark for acceptable outcomes in uncertain environments.

  • Search Strategies: Identifying options without exhaustive knowledge about all alternatives.

Ecological Rationality

  • Concept whereby the effectiveness of heuristics is evaluated based on their adaptiveness to the environmental structure.

  • Heuristics can outperform complex models under specific conditions, particularly in uncertain settings.


The adaptive tool box:

  • Set an expectation

  • Choose first option that satisfies expectations

  • After a time adjust expectation till new expectation is met

Conclusion

  • Bounded rationality reflects the limitations of human cognition and the importance of studying decision-making processes in real-world contexts rather than idealized models.

  • Simon's propositions have profound implications across disciplines, challenging the premises of mainstream economics and informing practices in management, psychology, and artificial intelligence.

References

  • An extensive reference list is included in the original document detailing key works and publications related to bounded rationality.