AI Wealth Truth (24): Why Your Intuition About Low-Probability Events Is Catastrophically Wrong

I. The brain's perception of probability is systematically distorted. We do not evaluate events by their true probabilities. We inflate small probabilities and compress large probabilities. This distortion is quietly draining your wallet.

II. Behavioral economics identified a pattern called the probability weighting function. When the true probability is 1%, the brain perceives it as about 5%. When the true probability is 99%, the brain perceives it as about 80%. We overestimate small probabilities and underestimate large probabilities.

III. This explains many seemingly contradictory behaviors.

IV. Why do people buy lottery tickets? The probability of a jackpot might be one in tens of millions. But the brain feels it as something like 1%. "What if I win?" drives the purchase. Lottery companies do not sell probability. They sell the illusion of "what if".

V. Why do people buy lottery tickets and insurance at the same time? Buying a lottery ticket is chasing risk. Buying insurance is avoiding risk. Is that contradictory? Not really. Both are driven by overestimating low-probability events. We overestimate winning (so we buy lotteries), and we overestimate disasters (so we buy insurance).

VI. Insurance companies understand this perfectly. They know what people fear. Plane crashes, kidnappings, rare diseases. They design specialized insurance products for these. The true probabilities are low, but the premiums are high, because your perceived probabilities are higher.

VII. Aviation accident insurance is a classic example. The probability of dying in a plane crash is about one in eight million. The probability of dying on the drive to the airport might be one in one hundred thousand. The latter is about 80 times higher. Yet people buy flight accident insurance, not "airport commute accident" insurance. You overreact to high-exposure risks and underreact to low-exposure risks.

VIII. Why do people fear terrorism more than heart disease? The probability of dying from heart disease is tens of thousands of times higher than dying from terrorism. But terrorism is heavily reported. Heart disease is not. The brain estimates probability by "how easy it is to recall examples". This is availability bias. Easy to recall becomes overestimated probability.

IX. How does overestimating small probabilities affect investing?

X. Impact 1: excessive fear of crashes. A 50% market crash is rare. But you fear it as if it will happen tomorrow. So you do not invest, or you over-allocate to low-return assets. You pay enormous opportunity costs to insure against a tiny-probability disaster.

XI. Impact 2: excessive chasing of explosive gains. The probability of a stock going 10x is small. But you think: "what if". So you put money into speculative assets. You chase a tiny-probability windfall and take a high-probability loss.

XII. Impact 3: ignoring high-probability risks. Inflation eats 3% of your purchasing power every year. The probability is close to 100%. But it is too boring for the brain to take seriously. The probability of a major illness is high for any individual, yet you feel "it won't be me". High-probability risks get ignored.

XIII. In the AI era, this bias is exploited precisely. AI learns which low-probability events best trigger your fear and greed. News recommendation algorithms prioritize dramatic events. Your information environment becomes saturated with low-probability, high-impact stories. That further distorts your probability perception.

XIV. Insurance sales uses AI too. It learns what you fear most and recommends matching products. "You recently searched for disease X? This policy covers it." AI amplifies your fear of small probabilities and sells you products.

XV. Investment apps exploit it as well. They push headlines about extreme surges and crashes. "Stock X jumped 50% in one day!" What you see is an outlier, but the brain treats it as typical. Every such push notification distorts your probability sense.

XVI. How do you correct probability distortion?

XVII. 1. Use numbers instead of feelings. Do not judge probability by intuition. Look up data. What is the plane crash probability? What is the car accident probability? Write the numbers down and force the brain to face reality. Feelings are unreliable. Numbers are more reliable.

XVIII. 2. Calculate expected value. Do not focus only on "what happens if it occurs". Focus on "probability times consequence". A lottery jackpot may be 10 million, but the probability is one in tens of millions. The expected value is negative. Expected value is the rational basis of decision-making.

XIX. 3. Anchor to base rates. Any prediction should start with base rates. What is the base success rate of startups? Around 10%. You think you are special? Fine. Maybe you are 15%. But not 90%. Anchor to base rates and avoid extreme estimates.

XX. 4. Beware availability bias. Easy to recall does not mean high probability. It often just means more media coverage and better stories. Ask yourself: am I worried because the true probability is high, or because I recently saw news about it? Separate exposure from probability.

XXI. 5. Buy insurance only for high-probability, high-loss risks. Medical insurance and critical illness insurance: probability is not low, and the loss is huge. Worth it. Flight accident insurance and phone screen insurance: probability is extremely low, and the loss is limited. Not worth it. Spend your money and attention on the risks that actually matter.

XXII. 6. Do not invest for low-probability jackpots. If the main selling point of an investment is "what if it goes 10x", it will most likely make you lose money. Sustainable wealth comes from high-probability positive returns, not low-probability windfalls.

XXIII. Your brain is not a calculator. It is a survival machine shaped by evolution in dangerous forests. Overestimating danger, small probability and big loss, improved survival. But in modern finance, this bias makes you choose badly. Evolutionary wisdom becomes a modern trap.

XXIV. There are two kinds of low-probability events. One kind you overestimate: plane crashes, terrorism, lottery jackpots. One kind you underestimate: systemic financial crises, technological disruption, personal health problems. By coincidence, what you overestimate often does not matter, and what you underestimate often matters a lot. The brain's probability calibration runs backward. In the AI era, this backward calibration is commercialized more thoroughly. You need to rely on data more than ever, not intuition.