An alphabetic tour of common behavioral biases that distract otherwise rational investors from making best choices about their wealth.
What is it? Anchoring bias occurs when you fix on or “anchor” your decisions to a reference point, whether or not it’s a valid one.
When is it helpful? An anchor point can be helpful when it is relevant to living more efficiently. For example, in his book, “The Behavioral Investor,” Daniel Crosby describes: “When you meet someone new you begin forming opinions of them within seconds. These first impressions, or anchors, then set the guardrails within which future impressions tend to fall.” As long as your assumptions hold true, they can speed things along next time you encounter the same individual.
When is it harmful? In investing, people often anchor on the price they paid when deciding whether to sell or hold a security: “I paid $11/share for this stock and now it’s only worth $9/share. I’ll hold off selling it until I’ve broken even.” Evidence-based investing informs us, the best time to sell a holding is when it’s no longer serving your ideal portfolio, as prescribed by your investment plans. What you paid is irrelevant to that decision, so anchoring on that arbitrary point creates a dangerous distraction.
What is it? Blind spot bias occurs when you can objectively assess others’ behavioral biases, but you cannot recognize your own.
When is it helpful? Blind spot bias helps you avoid over-analyzing your every imperfection, so you can get on with your one life to live. It helps you tell yourself, “I can do this,” even when others may have their doubts.
When is it harmful? It’s hard enough to root out all your deep-seated biases once you’re aware of them, let alone the ones you remain blind to. In “Thinking, Fast and Slow,” Nobel laureate Daniel Kahneman describes (emphasis ours): “We are often confident even when we are wrong, and an objective observer is more likely to detect our errors than we are.” (Hint: This is where second opinions from an independent advisor can come in especially handy.)
What is it? We humans love to be right and hate to be wrong. This manifests as confirmation bias, which tricks us into being extra sympathetic to information that supports our beliefs and especially suspicious of – or even entirely blind to – conflicting evidence.
When is it helpful? When it’s working in our favor, confirmation bias helps us build on past insights to more readily resolve new, similar challenges. Imagine if you otherwise had to approach each new piece of information with no opinion, mulling over every new idea from scratch. While you’d be incredibly open-minded, you’d also be excessively indecisive.
When is it harmful? Once we believe something – such as an investment is a good/bad idea, or a market is about to tank or soar – we want to keep believing it. To remain convinced, we’ll tune out news that contradicts our beliefs and tune into that which favors them. We’ll discount facts that would change our mind, find false affirmation in random coincidences, and justify fallacies and mistaken assumptions that we would otherwise recognize as inappropriate. And we’ll do all this without even knowing it’s happening. Even stock analysts can be influenced by this bias.
What is it? Familiarity bias is another mental shortcut we use to more quickly trust (or more slowly reject) an object that is familiar to us.
When is it helpful? Do you cheer for your home-town team? Speak more openly with friends than strangers? Favor a job applicant who (all else being equal) has been recommended by one of your best employees? Congratulations, you’re making good use of familiarity bias.
When is it harmful? Considerable evidence tells us that a broad, globally diversified approach best enables us to capture expected market returns while managing the risks involved. Yet studies like this one have shown investors often instead overweight their allocations to familiar vs. foreign investments. We instinctively assume familiar holdings are safer or better, even though, clearly, we can’t all be correct at once. We also tend to be more comfortable than we should be bulking up on our employer’s company stock.
What is it? You know what fear is, but it may be less obvious how it works. As Jason Zweig describes in “Your Money & Your Brain,” if your brain perceives a threat, it spews chemicals like corticosterone that “flood your body with fear signals before you are consciously aware of being afraid.” Some suggest this isn’t really “fear,” since you don’t have time to think before you act. Call it what you will, this bias can heavily influence your next moves – for better or worse.
When is it helpful? Of course, there are times you probably should be afraid, with no time for studious reflection about an urgent life-saving act. If you are reading this, it strongly suggests you and your ancestors have made good use of these sorts of survival instincts many times over.
When is it harmful? Zweig and others have described how our brain reacts to a plummeting market in the same way it responds to a physical threat like a rattlesnake. While you may be well-served to leap before you look at a snake, doing the same with your investments can bite you. Also, our financial fears are often misplaced. We tend to overcompensate for more memorable risks (like a flash crash), while ignoring more subtle ones that can be just as harmful or much easier to prevent (like inflation, eroding your spending power over time).
What is it? In “Thinking, Fast and Slow,” Nobel laureate Daniel Kahneman defines the effects of framing as follows: “Different ways of presenting the same information often evoke different emotions.” For example, he explains how consumers tend to prefer cold cuts labeled “90% fat-free” over those labeled “10% fat.” By narrowly framing the information (fat-free = good, fat = bad; never mind the rest), we fail to consider the facts as a whole.
When is it helpful? Have you ever faced an enormous project or goal that left you feeling overwhelmed? Framing helps us take on seemingly insurmountable challenges by focusing on one step at a time until, over time, the job is done. In this context, it can be a helpful assistant.
When is it harmful? To achieve your personal financial goals, you’ve got to do more than score isolated victories in the market; you’ve got to “win the war.” As UCLA’s Shlomo Benartzi describes in a Wall Street Journal piece, this demands strategic planning and unified portfolio management, with individual holdings considered within the greater context. Investors who instead succumb to narrow framing often end up falling off-course and incurring unnecessary costs by chasing or fleeing isolated investments.
What is it? Like fear, greed requires no formal introduction. In investing, the term usually refers to our tendency to (greedily) chase hot stocks, sectors, or markets, hoping to score larger-than-life returns. In doing so, we ignore the oversized risks typically involved as well.
When is it helpful? In Oliver Stone’s Oscar-winning “Wall Street,” Gordon Gekko (based on the notorious real-life trader Ivan Boesky) makes a valid point … to a point: “[G]reed, for lack of a better word, is good. … Greed, in all of its forms; greed for life, for money, for love, knowledge has marked the upward surge of mankind.” In other words, there are times when a little greed – call it ambition – can inspire greater achievements.
When is it harmful? In our cut-throat markets (where you’re up against the Boeskys of the world), greed and fear become a two-sided coin that you flip at your own peril. Heads or tails, both are accompanied by chemical responses to stimuli we’re unaware of and have no control over. Overindulging in either extreme leads to unnecessary trading at inopportune times.
What is it? Mooove over, cows. You’ve got nothing on us humans, who instinctively recoil from or rush headlong into excitement when we see others doing the same. “[T]he idea that people conform to the behavior of others is among the most accepted principles of psychology,” say Gary Belsky and Thomas Gilovich in “Why Smart People Make Big Money Mistakes.”
When is it helpful? If you’ve ever gone to a hot new restaurant, followed a fashion trend, or binge-watched a hit series, you’ve been influenced by herd mentality. “Mostly such conformity is a good thing, and it’s one of the reasons that societies are able to function,” say Belsky and Gilovich. It helps us create order out of chaos in traffic, legal and governmental systems alike.
When is it harmful? Whenever a piece of the market is on a hot run or in a cold plunge, herd mentality intensifies our greedy or fearful chain reaction to the random events that generated the excitement to begin with. Once the dust settles, those who have reacted to the near-term noise are usually the ones who end up overpaying for the “privilege” of chasing or fleeing temporary trends instead of staying the course toward their long-term goals. As Berkshire Hathaway Chairman and CEO Warren Buffett has famously said, “Investors should remember that excitement and expenses are their enemies. And if they insist on trying to time their participation in equities, they should try to be fearful when others are greedy and greedy only when others are fearful.”
What is it? In “Thinking, Fast and Slow,” Nobel laureate Daniel Kahneman credits Baruch Fischhoff for demonstrating hindsight bias – the “I knew it all along” effect – when he was still a student. Kahneman describes hindsight bias as a “robust cognitive illusion” that causes us to believe our memory is correct when it is not. For example, say you expected a candidate to lose, but she ended up winning. When asked afterward how strongly you predicted the actual outcome, you’re likely to recall giving it higher odds than you originally did. This seems like something straight out of a science fiction novel, but it really does happen!
When is it helpful? Similar to blind spot bias (one of the first biases we covered), hindsight bias helps us assume a more comforting, upbeat outlook in life. As “Why Smart People Make Big Money Mistakes” authors Gary Belsky and Thomas Gilovich describe it, “We humans have developed sneaky habits to look back on ourselves in pride.” Sometimes, this causes no harm, and may even help us move past prior setbacks.
When is it harmful? Hindsight bias is hazardous to investors, since your best financial decisions come from realistic assessments of market risks and rewards. As Kahneman explains, hindsight bias “leads observers to assess the quality of a decision not by whether the process was sound but by whether its outcome was good or bad.” If a high-risk investment happens to outperform, but you conveniently forget how risky it truly was, you may load up on too much of it and not be so lucky moving forward. On the flip side, you may too quickly abandon an underperforming holding, deceiving yourself into dismissing it as a bad bet to begin with.
What is it? “Loss aversion” is a fancy way of saying we often fear losing more than we crave winning. This leads to some interesting results when balancing risks and rewards. For example, in “Stumbling on Happiness,” Daniel Gilbert describes: “[M]ost of us would refuse a bet that gives us an 85 percent chance of doubling our life savings and a 15 percent chance of losing it.” Even though the odds favor a big win, imagining that smaller chance that you might go broke leads most people to decide it’s just not worth the risk.
When is it helpful? To cite one illustration of when loss aversion plays in your favor, consider the home and auto insurance you buy every year. It’s unlikely your house will burn to the ground, your car will be stolen, or an act of negligence will cost you your life’s savings in court. But loss aversion reminds us that unlikely does not mean impossible. It still makes good sense to protect against worst-case scenarios when we know the recovery would be very painful indeed.
When is it harmful? One way loss aversion plays against you is if you decide to sit in cash or bonds during bear markets – or when all is well, but a correction feels overdue. Evidence suggests you are expected to end up with higher long-term returns by at least staying put, if not bulking up on stocks when they are “cheap.” And yet, the potential for future loss can frighten us into abandoning our carefully planned course toward the likelihood of long-term returns.
What is it? If you’ve ever treated one dollar differently from another when assessing its worth, that’s mental accounting at play. For example, if you assume inherited money must be more responsibly managed than money you’ve won in a raffle, you’re engaging in mental accounting.
When is it helpful? In his early paper “Mental Accounting Matters,” Nobel laureate Richard Thaler (who is credited for having coined the term) describes how people use mental accounting “to keep trace of where their money is going, and to keep spending under control.” For example, say you set aside $250/month for a fun family outing. This does not actually obligate you to spend the money as planned or to stick to your budget. But by effectively assigning this function to that money, you’re better positioned to enjoy your leisure time, without overdoing it.
When is it harmful? While mental accounting can foster good saving and spending habits, it plays against you if you instead let it undermine your rational investing. Say, for example, you’re emotionally attached to a stock you inherited from a beloved aunt. You may be unwilling to unload it, even if reason dictates that you should. You’ve just mentally accounted your aunt’s bequest into a place that detracts from rather than contributes to your best financial interests.
What is it? Sometimes, good or bad outcomes are the result of good or bad decisions; other times (such as when you try to forecast future market movements), it’s just random luck. Outcome bias is when you mistake that luck as skill.
When is it helpful? This may be one bias that is never really helpful in the long run. If you’ve just experienced good or bad luck rather than made a smart or dumb decision, when wouldn’t you want to know the difference, so you can live and learn?
When is it harmful? As Kahneman describes in “Thinking, Fast and Slow,” outcome bias “makes it almost impossible to evaluate a decision properly – in terms of the beliefs that were reasonable when the decision was made.” It causes us to be overly critical of sound decisions if the results happen to disappoint. Conversely, it generates a “halo effect,” assigning undeserved credit “to irresponsible risk seekers …who took a crazy gamble and won.” In short, this is dangerous stuff in largely efficient markets. The more an individual happens to come out ahead on lucky bets, the more they may mistakenly believe there’s more than just luck at play.
What is it? No sooner do we recover from one debilitating bias, our brain can whipsaw us in an equally damaging but opposite direction. For example, we’ve already seen how fear on the one hand and greed on the other can knock investors off course either way. Similarly, overconfidence is the flip side of loss aversion. Once we’ve got something, we are averse to losing it, so we will overvalue it compared to its going rate. But when we are pursuing fame or fortune, or even going about our daily lives, we tend to be overconfident about our odds of success.
When is it helpful? In “Your Money & Your Brain,” Jason Zweig cites several sources that describe overconfidence in action and why it’s the norm rather than the exception in our lives. “How else could we ever get up the nerve to ask somebody out on a date, go on a job interview, or compete in a sport?” asks Zweig, and adds: “There is only one major group whose members do not consistently believe they are above average: people who are clinically depressed.”
When is it harmful? While overconfidence can be beneficial, it becomes dangerous when you’re investing. Interacting with a host of other biases (such as greed, confirmation bias, and familiarity bias) overconfidence puffs up our belief that we can consistently beat the market by being smarter or luckier than average. In reality, when it’s you, betting against the trillions and trillions of other dollars at play in our global markets, it’s best to be brutally realistic about how to patiently participate in the market’s expected returns, instead of trying to go for broke – potentially literally.
What is it? Is that a zebra, a cheetah, or a light breeze moving through the grass? Since prehistoric times when our ancestors depended on getting the right answer, right away, evolution has been conditioning our brains to find and interpret patterns – or else. That’s why, our pattern-seeking impulses tend to treat even random events (like 10 coin flips, all heads) as if they’re orderly outcomes suggesting a predictive pattern. “Just as nature abhors a vacuum, people hate randomness,” says Zweig, as a result of our brain’s dopamine-induced “prediction addiction.”
When is it helpful? When we stop at red lights and go on green, we’re making excellent use of pattern recognition. Is your spouse or partner giving you “that look”? You know just what it means before they’ve said a single word. And whether you enjoy a good jigsaw puzzle, Sudoku, or Rubik’s Cube, you’re giving your pattern recognition skills a healthy workout.
When is it harmful? Speaking of seeing red, Zweig published a fascinating piece on how simply presenting financial numbers in red instead of black can make investors more fearful and risk-averse. That’s a powerful illustration of how pattern recognition can influence us – even if the so-called pattern (red = danger) is a red herring. Is any given stream of breaking financial news a predictive pattern worth pursuing, or is it a deceptive mirage? Given how hard it is to tell the difference until hindsight reveals the truth, investors are best off ignoring the market’s many glittering distractions and focusing instead on their long-term goals.
What is it? Recency causes you to pay more attention to your most recent experiences, and to downplay the significance of long-term conditions. For example, in “Nudge,” Nobel laureate Richard Thaler and co-author Cass Sunstein observe: “If floods have not occurred in the immediate past, people who live on floodplains are far less likely to purchase insurance.” That’s recency, tricking people into ascribing more importance to the lack of recent flooding than to the bigger context of being located on a flood plain.
When is it helpful? In “Stumbling on Happiness,” Daniel Gilbert describes how we humans employ recency to accurately interpret otherwise ambiguous situations. Say, for example, someone says to you, “Don’t run into the bank!” Whether you’re currently floating down a river or approaching a financial institution helps you quickly decide whether to paddle harder in the stream, or walk more slowly through the financial institution’s door.
When is it harmful? Buying high and selling low is exactly the opposite of investors’ actual aspirations. And yet, no matter how many times our capital markets have moved through their bear-and-bull cycles, recency causes droves of investors to stumble every time. By reacting to the most recent jolts instead of remaining positioned as planned for long-term expected growth, they end up piling into high-priced hot holdings and locking in losses by selling low during the downturns. They allow recency to get the better of them, and their most rational, evidence-based investment decisions.
What is it? Sunk cost fallacy makes it harder for us to lose something when we also face losing the time, energy or money we’ve already put into it. In “Why Smart People Make Big Money Mistakes,” Gary Belsky and Thomas Gilovich describe: “[Sunk cost fallacy] is the primary reason most people would choose to risk traveling in a dangerous snowstorm if they had paid for a ticket to an important game or concert, while passing on the trip if they had been given the ticket for free.” You’re missing or attending the same event either way. But if a sunk cost is involved, it somehow makes it more difficult to let go, even if you would be better off without it.
When is it helpful? When a person, project, or possession is truly worth it to you, sunk costs – the blood, sweat, tears, and/or legal tender you’ve already poured into them – can help you take a deep breath and soldier on. Otherwise, let’s face it. There might be those days when you’d be tempted to help your kids pack their “run away from home” bags yourself.
When is it harmful? Falling for financial sunk cost fallacy is so common, there’s even a cliché for it: throwing good money after bad. There’s little harm done if the toss is a small one, such as attending a prepaid event you’d rather have skipped. But in investing, adopting a sunk cost mentality can prevent you from unloading an existing holding once it no longer belongs in your portfolio. For better or worse, you cannot go back in time and alter what you’ve already done with your investments. But you can (and should) keep your portfolio optimized for capturing future expected returns according to your own goals and the best evidence available to us today.
What is it? If you’ve ever decided the grass is greener on the other side, you’ve experienced tracking error regret – that gnawing envy you feel when you compare yourself to external standards, and wish you were more like them.
When is it helpful? If you’re comparing yourself to a meaningful benchmark, tracking error-regret can be a positive force, spurring you to try harder. Say, for example, you’re a professional athlete and you’ve been repeatedly losing to your peers. You may be prompted to embrace a new fitness regimen, rethink your equipment, or otherwise strive to improve your game.
When is it harmful? If you’ve structured your investment portfolio to reflect your goals and risk tolerances, it’s important to remember that your near-term results may frequently march out of tune with “typical” returns … by design. It can be deeply damaging to your long-range plans if you compare your own performance to irrelevant, apples-to-oranges benchmarks such as the general market, the latest popular trends, or your neighbor’s seemingly greener financial grass. Stop playing the shoulda, woulda, coulda game. Stop chasing past returns you wish you had received based on random outperformance others (whose goals differ from yours) may have enjoyed. You’re better off tending to your own fertile possibilities, guided by personalized planning, evidence-based investing, and accurate benchmark comparisons.