Formula
Pain of losing $100 ≈ 2× Pleasure of gaining $100
Compare
| Loss Aversion Effect | What Investors Do | Rational Alternative |
|---|---|---|
| Hold losers too long | Refuse to sell at a loss, hoping for recovery | Sell if thesis is broken regardless of P&L |
| Sell winners too early | Take profits at +10% to avoid giving back gains | Let winners run if fundamentals support higher prices |
| Avoid all risk | Stay in cash because markets ‘might crash’ | Accept volatility as the price of long-term returns |
| Disposition effect | Net result: portfolio of losers, sold all winners | Costs 2–4% annually in risk-adjusted returns |
Key point
The disposition effect (selling winners, holding losers) is the single most expensive behavioral bias for individual investors. It’s driven purely by loss aversion — the pain of realizing a loss is so intense that investors avoid it at any cost.
Try it
Review your trade history. Have you ever held a losing position far longer than a winning one? Have you sold a stock at +15% that later went up 100%? These are loss aversion signatures.
Check-in
A stock you own is down 30%. The fundamentals have deteriorated. You think ‘I’ll sell when it gets back to even.’ What’s wrong with this thinking?
Key insight
Check your understanding
Sit with the ideas.
You hold two positions: Stock A is up 40% with strengthening fundamentals; Stock B is down 25% with weakening fundamentals. You need to raise cash by selling exactly one. Which do you sell?
Why: