Availability Heuristic: Overview, Bias, and Examples

The availability heuristic is a mental shortcut where people judge how likely something is by how easily examples come to mind. Heuristics in general help us make decisions when time or information is limited—the availability heuristic does this by treating easily recalled information as more important and more probable than it really is.

It explains, for example, why many people overestimate their probability of winning the lottery. People usually buy more tickets after someone wins a large jackpot, even though the odds haven’t changed. The positive news is fresh in their minds, so winning feels more likely.

How the availability heuristic works

When you make a decision, a recent memory of a similar situation often springs to mind first. Most people assume that if something is easy to remember, it must be important—so they give that information extra weight and overestimate the likelihood of similar events happening again.

Even when all the relevant information is available, the availability heuristic can shortcut the decision-making process and go with whatever comes to mind quickly. After watching a news report about robberies, for example, you might conclude robberies are far more common in your area than they are. You arrive at a decision fast, but at the expense of careful thought.

Examples of the availability heuristic

Here are some scenarios where the availability heuristic plays out in day-to-day life:

Safety

People often overestimate the risk of events like plane crashes, terrorist attacks, or contracting a rare disease, while underestimating the risk of car crashes and cancer. Sensationalized media coverage is usually the culprit—vivid images and examples come to mind readily, so the risk feels bigger.

Insurance rates

There’s usually a spike in insurance purchases after disasters like hurricanes, floods, or earthquakes. These events receive extensive media coverage and stay readily available in people’s minds, making disasters feel more frequent than they are. More people seek coverage, prompting insurance companies to adjust their rates.

Word frequency

It’s easier to think of words starting with the letter k than words with k as the third letter, so most people assume the first category is bigger. In fact, there are about twice as many words with k as the third letter. The availability heuristic leads to a predictable error.

How does the availability heuristic create bias?

The availability heuristic is sometimes called the availability bias. A bias is an inclination toward or against someone or something that isn’t based on fact or reason.

When you make decisions based on the availability heuristic, you rely more on emotion, feeling, or intuition than fact. Ease of recall is a useful rough guide to probability, but it often leads to bias because you skip over important factors.

Avoiding the availability heuristic improves decision-making

The availability heuristic lets you make decisions quickly, but it also increases the likelihood you’ll make bad ones. It keeps you stuck in the same cognitive-bias mentality.

You can mitigate its effects by considering all the useful data when making decisions under uncertainty—not just the information that comes readily to mind.

Once you can recognize how the availability bias influences your first thoughts, you can pause, evaluate all the available data, and make a more informed decision.

Examples of decisions using the availability heuristic in the workplace

The availability heuristic can affect workplace decisions in ways like these:

Deciding who to promote to a new leadership position

Say a manager wants to promote an employee to a leadership position and has narrowed it down to two candidates. Both are qualified, have good leadership skills, and have made similar mistakes in the past. The first candidate once forgot to deliver an important package before going on a trip. The second made the same kind of mistake while working directly for the hiring manager.

The manager remembers the second candidate’s mistake more vividly and, due to the availability heuristic, gives it more weight. They intuitively promote the first candidate, even though both made essentially identical mistakes.

Considering new employment opportunities

Imagine you’re planning to leave your current job. Your company recently made budget cuts that cost several of your coworkers their jobs, and you were demoted to your old position. You then read about similar experiences at the company you plan to join.

Since those events didn’t directly affect you, and the memory most available in your mind is your recent demotion, you may still prefer to switch—believing your chances of losing the new job are low. In reality, the new firm isn’t necessarily a safer choice, since it has the same employee retention problems as your current employer.

Practical tips for overcoming the availability bias

Here are some ways to overcome the availability heuristic and make more informed decisions:

Avoid making impulse decisions or judgments

Whenever you have to make a quick decision, take some time to think it through. Ask yourself what’s informing the decision and where your judgment of the situation comes from.

Say you’re booking a hotel for an upcoming conference. Your company has used that hotel before and received good service. But as you’re about to call, you remember a family member’s recent story about a bad experience at a hotel in the same chain, in a different location.

If you follow the availability heuristic, you might organize the conference elsewhere. Pause and consider all the facts instead. You may know the family member tends to exaggerate, and your company has never complained about this chain. On balance, the chances of a bad experience are low.

Clear out your echo chambers

To make objective decisions, seek out information sources that don’t necessarily agree with your beliefs. Get news updates from somewhere other than your favorite outlet, for example. If you only consume data from sources aligned with your beliefs, they’ll just reinforce them. Think critically by seeking different points of view and challenging your own biases.

Watch overall trends and patterns

Recent events can distort your perception of reality, but long-term patterns and trends often tell a different story. Say you’re a manager with an employee who’s been coming to work late. Before deciding what to do, look at their history. If they’ve rarely been late in previous years, it may be a short-term issue—ask how you can support them. If the pattern shows they’ve been regularly late throughout their time at the company, you may need a different approach.

Consider overall statistics

Knowing a few left-handed people doesn’t mean most people in the world are left-handed. Don’t rely on the people close to you when estimating the probability of something. Research the base rate instead—the people in your life form a small sample that doesn’t reflect reality.

Related cognitive biases

Representativeness bias

Representativeness bias happens when we estimate the probability of an event based on its similarity to a known situation. For example, customer service representatives may assume customers from a certain demographic or age group have specific preferences based on stereotypes, instead of approaching them as individuals with unique needs.

Anchoring/adjustment bias

Anchoring bias, or adjustment bias, occurs when you use a single piece of information to make a decision or solve a problem. People often make inaccurate estimates because they don’t adjust far enough from their initial value.