Neglect of Probability
We disregard probability when making decisions under uncertainty.
Neglect of probability, a type of cognitive bias, is the tendency to completely disregard probability when making a decision under uncertainty. Small risks are either completely ignored or overly inflated, without consideration of the actual likelihood. Fear of plane crashes (low probability, high consequence) vs. fear of car crashes (high probability, similar consequence) demonstrates this bias in action.
What it looks like in the wild.
- Everyday life Lottery Playing People regularly play lotteries with 1-in-300-million odds while refusing to invest in index funds with historically positive expected returns.
Someone has already built a business on this.
Biases are not only private errors. They are design targets — patterns deliberately engineered into interfaces because they reliably work.
- Games Loot Box Probability Obscuring Video games deliberately obscure the extremely low probability of rare item drops from loot boxes, exploiting probability neglect to drive purchases.
Recognising a definition is not the same skill as spotting it.
Two scenarios from the app, with distractors drawn from the same family of biases — which is what makes them hard.
Mia is choosing between two job offers. She focuses on the higher salary of Offer A, completely ignoring that Offer B's industry has a 90% five-year survival rate while Offer A's is only 30%.
Isabella chooses not to get flood insurance for her house in a flood zone because she believes the river won't rise that high this year, despite historical data showing frequent floods.
Biases rarely arrive alone.
Understand more. Assume less.
188 biases, 18,869 scenarios, and a record of how you actually decide.
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