Availability Heuristic
We judge probability by how easily examples come to mind.
Explanation
If you can quickly think of examples of something happening, your brain assumes it happens frequently. Recent, dramatic, or personally experienced events feel more likely than they actually are. This is why people overestimate rare but memorable risks (shark attacks) and underestimate common but forgettable ones (heart disease).
Real-World Example
After plane crash news, people avoid flying even though driving is statistically more dangerous—car accidents don't make headlines. Entrepreneurs overestimate startup success rates because they constantly hear about successful companies, not the 90% that fail quietly. People overestimate crime rates in neighborhoods where they personally witnessed incidents.
How to Apply
When assessing risks: Look up actual statistics, don't rely on memory. Recent news distorts perception—zoom out to longer time periods. Consider silent failures you don't hear about. Ask: 'What examples am I NOT thinking of?' Base important decisions on data, not memorable anecdotes.