Table of Contents
Why do we make irrational financial decisions during competitive bidding?
Explore Richard Thaler’s behavioral economics insights to understand why we overpay in auctions, cling to possessions, and make irrational financial decisions.
Continue reading to see how these behavioral anomalies impact your wallet and learn practical ways to navigate competitive markets with a clear head.
Genres
Psychology, Economics, Personal Development
Learn when economists get things wrong.
The Winner’s Curse (2025) revisits influential essays on behavioral economics originally published decades ago, examining how these findings about human economic irrationality have held up over time. It demonstrates that people consistently deviate from the rational economic behavior predicted by traditional theory, making systematic errors across the board, from auctions and financial markets, to everyday transactions.
Over 30 years ago, Richard Thaler threw a wrench into the machinery of economic theory. Writing alongside legends like Daniel Kahneman and Amos Tversky, he published a series of articles called Anomalies, in which he showed that people aren’t the cold, calculating optimizers economists had assumed. Instead, we’re wonderfully irrational creatures driven by emotions, biases, and mental shortcuts.
Now, Thaler has teamed up with economist Alex Imas to revisit those groundbreaking discoveries, and provide fresh insight into them. This summary will lead you through a select few of these anomalies.
You’ll learn why we cooperate when we shouldn’t, how we value things differently depending on how questions are framed, and how we let ownership cloud our judgment. You’ll also see how financial markets – supposedly the most rational arena of all – regularly violate their own fundamental laws.
Ready to rethink behavioral economics? Let’s get started.
The winner’s curse
Next time you’re at a party, try this little trick. Take a jar of coins, auction it off to your friends after a few drinks, and you’ll witness two contradictory things happening at once. The average bid will fall safely below the jar’s actual value, because most people don’t want to risk overpaying. But the person who actually wins? They’ll almost certainly pay more than those coins are worth.
This is the winner’s curse in action, and its implications stretch far beyond parlor games.
Oil company Atlantic Richfield discovered this the hard way. It kept winning government auctions for drilling rights, only to find that its sites consistently contained less oil than its expert engineers had predicted. Something wasn’t adding up. The company was winning auctions, yes – but at what cost?
The answer lies in understanding what’s really happening when you bid. You’re not simply estimating an object’s value in isolation. You’re making a calculation that depends entirely on the other people in the room. When competition intensifies and more bidders appear, the natural instinct is to bid more aggressively to secure the win. But here’s the counterintuitive truth: that’s exactly when you should pull back. More bidders mean a higher chance that someone will overestimate the value, and if you win in that environment, you’re probably that someone.
Yet we rarely see people adjust their behavior this way. Book publishers routinely pay advances that never get recouped. Companies overpay for acquisitions that disappoint shareholders. The pattern repeats itself endlessly across industries.
This creates a serious problem for traditional economic theory, which assumes we’re all rational agents making optimal decisions. But rationality isn’t something that automatically spreads through a population just because some economist proved a theorem. Most of us operate on what’s called k-level thinking – we believe we’re one step ahead of everyone else in our reasoning. We think we’re being clever while making the same mistakes as our competitors.
The real world of human decision-making looks nothing like the pristine models in economics textbooks. We’re pattern-seeking, overconfident, and prone to systematic errors. Understanding this gap between theory and reality is crucial.
So next time you find yourself in competitive bidding – whether for a house, a business, or just that jar of coins – pause and look around. How many other bidders are there? How economics-savvy are they? How sober are they? The more crowded the auction, the more cautiously you should proceed. Because sometimes the real victory is knowing when not to win.
Selfishness vs cooperation
Traditional economic theory rests on two key assumptions about human nature: we’re rational calculators, and we’re completely selfish. We act purely in our own self-interest, maximizing personal gain at every opportunity. It’s a tidy model – but like many tidy models, it often crashes and skids when it meets the real world.
Consider public goods: parks, clean air, community resources. These cost roughly the same to provide whether one person uses them or a thousand do, and it’s nearly impossible to exclude non-contributors from enjoying them. Economic theory makes a stark prediction here. Given the opportunity, virtually everyone will free-ride – enjoying the benefits without contributing a dime. Why pay for something you can get for free?
To test this, researchers created the public goods game. Participants receive an initial sum of money and decide how much to contribute to a common pot. That pot gets multiplied and redistributed equally among everyone. The rational, selfish move is crystal clear: contribute nothing, let others chip in, and pocket both your original stake and your share of the collective pot.
But here’s what actually happens: anonymous strangers consistently contribute between 40 and 60 percent of their money. Not occasionally. Consistently.
So why do people cooperate when theory says they shouldn’t?
One explanation is reciprocal altruism – the idea that cooperation is actually a disguised form of self-interest. People recognize that failing to cooperate will hurt them long-term, so they play nice. It’s a useful framework, but it doesn’t explain why people still cooperate in one-off experiments where there’s no future payoff.
Another theory – altruism – suggests that cooperation itself generates pleasure. We’re still being “selfish” in this view, just pursuing a more subtle utility function than simple monetary gain.
Perhaps most intriguing is the power of communication. When groups can discuss their choices beforehand, cooperation skyrockets – especially when people make promises to each other. Something about the act of talking and making commitments fundamentally changes behavior.
So, how should we think about public goods and the problem of free-riding? There’s a telling example of a group of farmers in the rural areas around Cornell University who once left fresh produce on roadside tables with a slotted box chained down for payment. No supervision, just an honor system with minimal safeguards. And by all appearances, it worked.
This captures the nuanced reality. Yes, some people will free-ride. But many will also contribute willingly, even when they don’t have to. Rather than forcing human behavior into rigid theoretical frameworks, perhaps we should embrace this complexity. People aren’t purely rational or selfish. We’re something messier and more interesting – creatures capable of both calculation and generosity, often in ways we can’t fully predict or explain.
The endowment effect
While Richard Thaler was at graduate school, one of his advisors revealed a peculiar paradox. He owned some bottles of Bordeaux wine he’d purchased for under $25 that had appreciated to $200 at auction. When asked if he’d sell them, he declined – $200 wasn’t enough. But would he buy more bottles at that price? Absolutely not. Too expensive.
Think about that for a moment. If the wine wasn’t worth buying at $200, why was it not worth selling at that price? This contradiction – which even an economist couldn’t escape – is called the endowment effect. We assign more value to things simply because we own them. And it creates a serious crack in traditional economic theory, which assumes that the most a consumer is willing to pay for an object should be roughly the same as the least they’re willing to accept to sell it.
Two psychological forces create this effect. The first is loss aversion – the pain of losing something outweighs the pleasure of gaining that same thing. This asymmetry shows up in unexpected places. Professional golfers on the PGA tour, for instance, are more likely to miss putts for birdie than for par, even though every stroke counts equally toward their tournament score. Why? Par serves as a reference point, making the potential loss of missing par feel worse than the potential gain of making birdie. So these elite athletes end up trying harder on par putts, despite the irrationality.
The second force is status quo bias – our tendency to keep things as they are unless pushed to change. Like Newton’s law of inertia applied to human behavior, we remain at rest until acted upon by external force. Subscription services understand this perfectly, which is why they auto-renew and count on our resistance to cancel.
Together, these biases create the endowment effect, and its implications are significant. Economic models need recalibrating – willingness to accept should be expected to run about twice as high as willingness to pay.
For the rest of us navigating daily decisions, there’s a useful diagnostic question you can ask yourself: Would I buy this at current market price if I didn’t already own it? If not, you’re probably clinging to it because of the endowment effect rather than its actual value. We’re not the rational calculators that economic theory imagines. We’re creatures deeply attached to what we have, fearful of loss, and stubbornly resistant to change – even when change makes perfect sense.
Preference reversals
We’ve seen how economic theory stumbles when predicting behavior. But now we’re going deeper – to cases where rationality itself simply breaks down.
Rationality in economics demands logical consistency. If you prefer bananas to apples, you shouldn’t also prefer apples to bananas. That would be preference reversal – a fundamental inconsistency. And yet preference reversals happen all the time.
Economists first noticed this with gambling experiments. Participants faced two options: a high bet with near-certain odds of winning a small amount, say $4, and a low bet with slim chances of winning a large amount, say $40. When asked which they preferred, most chose the high bet – the safe, easy win. But then came the twist. When asked to assign a dollar value to each bet, most participants put a higher price on the low bet. That’s a direct contradiction. They preferred one option but valued the other more highly.
So what’s going on? One explanation is stimulus-response compatibility. Think about your stove’s burners. Ever turn the wrong knob? That happens because the spatial arrangement of the knobs doesn’t match the burners. When they’re both arranged in a square, control becomes intuitive. In a similar way, people respond more strongly to attributes that match the format of the question being asked.
In the gambling experiment, both the bet outcomes and the valuation question were expressed in dollars. So when participants assigned dollar values, they focused heavily on the dollar amounts – gravitating toward the bet with the bigger potential payout. But when simply stating a preference, those dollar figures carried less weight, and the high probability of winning mattered more.
The way a question is framed shapes our preferences. So does the difference in context between making choices and experiencing them. Consider music playlists. When assembling one, most people opt for variety, imagining it will make listening more interesting. But when they actually sit down to listen, that variety feels less pleasant than anticipated, and they start skipping tracks that break the vibe. This is called diversification bias – we tend to opt for more variety when making a choice, even though we might not enjoy that variety later.
It’s plain to see, then, that our choices aren’t consistent, much to the frustration of economists trying to model human behavior. But recognizing this inconsistency can be useful. Next time you decide you prefer one option over another, pause and ask yourself: Would I also pay more for that option? If not, you might need to reconsider what you actually value.
The law of one price
Physics has gravity. Biology has natural selection. These fundamental laws help us understand how the world works. But what about economics? Surely a field that shapes trillions of dollars in daily transactions must rest on equally solid ground.
Enter the law of one price – perhaps the most fundamental principle in all of finance. It states that in competitive markets without barriers or transaction costs, identical goods must sell for identical prices. Simple, elegant, seemingly unbreakable. Financial markets appear to be the perfect testing ground: competitive, liquid, with minimal friction. If the law holds anywhere, it should hold there.
Now, if identical assets traded at different prices, investors could engage in arbitrage – buying low and selling high quasi-simultaneously, making risk-free profits. In financial theory, this can’t persist. Savvy investors would exploit these discrepancies endlessly, buying cheap securities and immediately flipping them for more, over and over. The opportunity should vanish almost instantly.
Except it doesn’t always.
Consider American Depository Receipts, or ADRs – shares in foreign companies held in trust by US financial institutions and traded on the New York Stock Exchange. They’re essentially the same as the underlying foreign shares, just more convenient for American investors. At one point in 2000, ADRs for Infosys, an Indian IT company trading in Bombay, were selling at a stunning 136 percent premium – more than double the price of the identical shares in India. The violation of the law of one price was glaring – although it could be partly explained by official barriers which prevented easy arbitrage.
Even more striking is the case of Royal Dutch/Shell twin shares. The group once had two share classes: Royal Dutch traded in Amsterdam, Shell in London. A 1907 agreement split all cash flows 60/40 between them. Mathematics is clear here – Royal Dutch shares should always trade at exactly 1.5 times the Shell price. Same company, fixed ratio, no ambiguity.
Yet the ratio fluctuated wildly throughout history. By the late 1990s, the two were trading roughly at par – nowhere near the 1.5-to-1 ratio they should have maintained. And here’s the kicker: there were no restrictions preventing arbitrage. Anyone could have exploited this discrepancy. But the mispricing persisted anyway.
So what does this tell us? If financial markets can’t even get straightforward cases like Royal Dutch/Shell right – literal no-brainers where the correct price is mathematically determined – what else are they getting wrong? The idea that stock prices reflect intrinsic value suddenly looks shaky. These are direct violations of what’s supposed to be an ironclad law, happening in plain sight in the world’s most sophisticated markets.
Conclusion
The main takeaway of this summary to The Winner’s Curse by Richard H. Thaler and Alex O. Imas is that economic theory’s assumptions about human rationality consistently crumble when confronted with reality.
The winner’s curse shows how competitive bidding leads us to overpay, while research on public goods reveals that people cooperate far more than pure self-interest would predict. The endowment effect demonstrates how ownership warps our sense of value, making us cling to possessions we’d never buy at market price. Preference reversals expose how the framing of questions fundamentally alters our choices in ways we don’t recognize. And perhaps most strikingly, violations of the law of one price in financial markets – even in simple cases like Royal Dutch/Shell twin shares – reveal that even the most sophisticated markets contradict economic predictions.
Together, these anomalies paint a picture of human decision-making that’s far messier, more emotional, and more interesting than traditional economics acknowledges.