Concept Library

Behavioral science concepts

Biases, heuristics, and conceptual frameworks, each with a real example of how it applies.

Fundamentals

System 1 and System 2

Our mind decides in two modes: one fast and intuitive, the other slow and deliberate.

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Fundamentals

Satisficing

We don't look for the best possible decision, just a good enough one.

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Fundamentals

Nudge

A change in how a decision is presented, without banning any option.

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Fundamentals

Choice Architecture

The context in which a choice is presented changes what we choose.

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Heuristics and biases

Salience

What contrasts with its surroundings captures our attention first.

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Heuristics and biases

Framing Effect

The same information, presented differently, changes the decision.

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Heuristics and biases

Peak-End Rule

We judge an experience by its most intense moment and how it ends.

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Heuristics and biases

Anchoring Bias

The first number you see changes how you perceive every number after it.

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Heuristics and biases

Affect Heuristic

We decide guided by how something makes us feel, not just its logic.

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Heuristics and biases

Confirmation Bias

We look for information that confirms what we already believed.

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Heuristics and biases

Loss Aversion

Losing something hurts us more than gaining the same thing pleases us.

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Heuristics and biases

Availability Heuristic

We judge how likely something is by how easily we can recall it.

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Heuristics and biases

Sunk Cost Fallacy

We keep investing in something just because we already invested before.

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Heuristics and biases

IKEA Effect

We value more highly what we helped build with our own hands.

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Heuristics and biases

Endowment Effect

We demand more in exchange for something that's already ours.

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Heuristics and biases

Halo Effect

One positive quality makes us assume others we haven't actually seen.

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Heuristics and biases

Hindsight Bias

Once something happens, it feels like it was predictable from the start.

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Heuristics and biases

Present Bias

We disproportionately value immediate rewards.

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Heuristics and biases

Dunning-Kruger Effect

The less we know about something, the worse we are at gauging how much we know.

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Heuristics and biases

Mere Exposure Effect

We start liking something more just because it becomes familiar.

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Heuristics and biases

Planning Fallacy

We systematically underestimate how much time and cost a task will take.

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Heuristics and biases

Optimism Bias

We believe things will go better for us than for everyone else, even without evidence for it.

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Heuristics and biases

Base Rate Neglect

We ignore the background probability and get carried away by the specific case.

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Heuristics and biases

Gambler's Fallacy

We believe luck "evens out" in the short run, even though each event is independent.

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Heuristics and biases

Illusion of Control

We overestimate how much we can influence outcomes that actually depend on chance.

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Heuristics and biases

Negativity Bias

Bad weighs more heavily on our minds than good, even at the same magnitude.

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Heuristics and biases

Barnum Effect

We accept vague personality descriptions as accurate if we feel they're talking about us.

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Social influence

Scarcity

What's about to run out automatically becomes more desirable.

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Social influence

Social Proof

When we don't know what to do, we look at what everyone else is doing.

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Social influence

Commitment Devices

Committing in front of others increases the odds we'll follow through.

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Social influence

Foot-in-the-Door Technique

Agreeing to a small request opens the door to agreeing to a bigger one.

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Social influence

Messenger Effect

Sometimes who says it matters more than what they say.

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Social influence

Reciprocity

Receiving something unrequested predisposes us to return the favor.

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Behavioral Design

Operational Transparency

Seeing the effort behind a service makes us value it more.

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Behavioral Design

Default Effect

We stick with whichever option comes pre-selected.

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Behavioral Design

Perceived Control

Feeling like we can cancel whenever we want makes us decide with more confidence.

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Behavioral Design

Processing Fluency

What's easy to process, we like more.

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Fundamentals

Cognitive Dissonance

We rationalize after acting against our own beliefs.

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Fundamentals

EAST Framework

Four simple questions for designing any behavioral intervention.

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Fundamentals

Sludge

The friction that makes it hard to access something that's technically already yours.

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Fundamentals

Mental Accounting

We treat money in separate categories instead of as something fungible.

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Behavioral Design

Decoy Effect

An inferior third option changes what we choose between the other two.

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Behavioral Design

Choice Overload

Too many options reduce the likelihood of deciding at all.

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Behavioral Design

Goal-Gradient Effect

Motivation increases the closer we get to the goal.

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Behavioral Design

Temptation Bundling

Tying a costly activity to a pleasurable one improves follow-through.

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Which of these concepts is at play in your product?

Download our guide "La ciencia de la persuasión" (in Spanish) with real cases of how 16 of them are applied.