Smart Heuristics
Smart heuristics are simple, fast, and frugal decision-making strategies that ignore information to make good decisions under uncertainty, contrary to the ideal of optimization. They demonstrate that less information can lead to better outcomes in many real-world situations.
THE IDEA
Introduction
Psychologist Gerd Gigerenzer challenges the traditional view that more information always leads to better decisions. He argues that in an uncertain world, optimal solutions are often unknown, and people can make good decisions using simple heuristics that ignore information. This perspective contrasts both with the idea of the mind as a cognitive optimizer and as a cognitive miser.
Key Examples
Gaze Heuristic for Catching a Ball
When a ball comes in high (in baseball, cricket, or soccer), players use a simple heuristic: they fixate on the ball and adjust their running speed so that the angle of gaze remains constant. This allows them to ignore all other variables like initial velocity, distance, and wind, and still catch the ball. The same heuristic is used by dogs catching frisbees.
Medical Decision Making: Base Rate Neglect
Physicians often misinterpret test results due to innumeracy with probabilities. For example, in mammography screening: if the base rate of breast cancer is 1%, the test sensitivity is 90%, and the false-positive rate is 9%, many doctors think a positive test implies a 90% chance of cancer. However, if you use natural frequencies: out of 100 women, 1 has cancer and tests positive, and about 9 out of 99 without cancer also test positive. Thus, only about 1 in 10 positive tests actually indicates cancer. This reframing helps avoid unnecessary panic or drastic actions.
Recognition Heuristic
When choosing between two objects (cities, stocks, products), if one is recognized and the other is not, the recognized one is often superior. For example, German students, who recognized San Diego but not San Antonio, correctly identified San Diego as larger (100% accuracy), while American students, who knew both, had lower accuracy. Similarly, in stock markets, portfolios of top-recognized stocks selected by laypeople sometimes outperform the market and mutual funds.
Core Concepts
- Fast and Frugal Heuristics: Decision strategies that use minimal time and information.
- Ecological Rationality: Heuristics are not inherently good or bad; their success depends on the structure of the environment.
- Natural Frequencies: Representing information as frequencies rather than probabilities often clarifies reasoning.
- Bounded Rationality: Human decision-making is constrained by limited time, information, and cognitive capacity.
Practical Implications
Gigerenzer’s work has applications in medicine (improving risk communication), finance (simple investment strategies), and everyday life (making choices under uncertainty). Understanding smart heuristics can help people become more literate about uncertainty and avoid both overconfidence and irrational fears.
When to use it
Making medical decisions after a positive test result (e.g., mammogram, PSA) by reframing probabilities as natural frequencies.
Choosing between two job offers using a single dominant reason that aligns with your core values.
Deciding which stock to invest in based on name recognition when you have limited knowledge of the market.
Quickly selecting products in a supermarket by relying on brand familiarity.
FROM THEORY TO EVERYDAY LIFE
In practice
Gaze Heuristic for Catching a Ball
When a ball is thrown high in the air, players fixate on it and adjust their running speed to keep the angle of gaze constant. This simple strategy works without complex calculations about trajectory or wind. It has been observed in baseball, cricket, soccer, and even in dogs catching frisbees.
Mammography Screening and Base Rate Fallacy
A 40-year-old woman receives a positive mammogram. The base rate of breast cancer is 1%, the test sensitivity is 90%, and the false-positive rate is 9%. Many physicians mistakenly conclude the chance of cancer is 90%, but using natural frequencies reveals it is only about 10%. This example shows how representation of information affects understanding.
Recognition Heuristic in Stock Picking
In a study, laypeople were asked which stocks they recognized. Portfolios of the most-recognized stocks (by ordinary citizens) outperformed randomly selected stocks, low-recognition stocks, and often even the market and mutual funds over six months. Name recognition can be a valid heuristic for investment.
A MOMENT TO REFLECT
Put it to work.
How can you apply the gaze heuristic to simplify complex tracking tasks in your daily life?
In what situations might ignoring information be beneficial, and when could it lead to costly mistakes?
How does the recognition heuristic influence your choices in buying products or making investments? How might you counteract it when necessary?
Often confused with
References
- Calculated Risk — Gerd Gigerenzer (2002)
- Gut Feelings — Gerd Gigerenzer (2007)
- Risk Savvy — Gerd Gigerenzer (2014)
- Simple Heuristics That Make Us Smart — Gerd Gigerenzer, Peter M. Todd, and the ABC Research Group (1999)
CONTINUE THE CONVERSATION
Source texts
- Thinking The New Science of Decision (John Brockman)