What Confirmation Bias Does to Your Trades
Imagine you have put on a trade you believe in. Maybe you are convinced a certain stock is the next big winner. Suddenly, every news headline or tweet that supports your bullish view jumps out at you. It feels great to see “evidence” that you are right. Meanwhile, any negative reports about that stock barely register or you quickly dismiss them as “noise.” Sound familiar? This is confirmation bias at work. It is like wearing mental blinders that let in only the information you want to see. As a result, you end up with a one-sided view of the market, which can lead to costly mistakes.
Confirmation bias is the tendency to seek out or interpret information in a way that confirms our pre-existing beliefs.
For traders and portfolio managers, that means once you have a thesis such as “XYZ is going to skyrocket” or “this strategy is foolproof,” you unintentionally start filtering the world. You highlight data that confirms your thesis and downplay or ignore data that challenges it. The problem is that markets do not care about your thesis. By cherry-picking information, you are effectively sabotaging your own trade. You might hold onto a losing position far too long because you only paid attention to the optimistic analysis and ignored clear warnings. Or you could double down on a bad bet, convinced that you are right and the market is wrong.
In short, confirmation bias turns normally rational traders into their own worst enemy by warping decision-making when it matters most.
Why Your Brain Loves Being Right (and How That Hurts Your Trading)
Why do smart traders fall into this trap? The answer lies in both neuroscience and psychology working hand in hand.
Simply put, your brain loves being right. On a neural level, when you encounter information that validates your belief such as a report saying the stock you bought is a “Strong Buy,” your brain’s reward center kicks in. It can release dopamine, the same chemical that makes you feel good when you win a game or eat your favorite food. It is a little burst of “Yes, I knew it!” that feels deeply satisfying.
This hit of pleasure reinforces your confidence in the trade. Naturally, you start gravitating toward more of that good feeling, seeking additional news or opinions that agree with you. It is a self-reinforcing cycle. The more confirmation you get, the better you feel, and the more certain you become that you are on the right track.
On the flip side, encountering information that contradicts your belief triggers the opposite reaction. Psychologically, it is uncomfortable to be wrong, so uncomfortable that it sets off alarm bells in your brain. When you read an analysis that tears apart the stock you were so bullish on, you might feel anxiety or even a flash of anger.
Neurologically, this is your amygdala (the brain’s emotional alarm center) lighting up, perceiving a threat. In high-stress moments, your body may release cortisol (a stress hormone), which can hijack your ability to think clearly and rationally. Essentially, your brain interprets “You might be wrong” as a danger to be avoided.
In psychological terms, it is known as avoiding cognitive dissonance, the mental discomfort of holding a belief that is being challenged by facts. To escape that discomfort, we often choose the easy route, which is to cling to our original belief and push away the contradicting evidence.
The kicker is that this all happens largely on a subconscious level. You are not trying to ignore reality. Your brain is doing it behind the scenes to protect your ego and keep you feeling good. It is an evolutionary hand-me-down that helped our ancestors make quick decisions without second-guessing too much.
But in the complex world of trading, that wiring can backfire badly. The very same “feel good” circuitry and protective instinct can lead you to double down on a doomed trade or miss the early signs of a trend change. Your brain’s love of being right can blind you to being effective, and making money is about being correct in reality, not just feeling correct in your head.
Spotting the Confirmation Bias Trap
The first step to overcoming confirmation bias is recognizing when it is happening to you. As a coach, I often tell traders to watch for a few telltale warning signs in their thinking and behavior:
- Selective Hearing or Reading: Be honest. Are you regularly skipping over articles, research reports, or chat messages that contradict your view? Do you find yourself saying, “Yeah, but…” whenever you encounter an opposing opinion? If you are only tuning in to information that sings your praises and tuning out the rest, that is a red flag.
- Defensiveness or Justifying: Pay attention to your emotional reactions. Do you get defensive when someone questions your position? Do you immediately start justifying why you are still right instead of considering they could have a point?
- Overconfidence in Your Thesis: You might notice you feel certain about a trade, so much that you stop actively monitoring for risks. If you catch yourself thinking “There is no way I am wrong on this one” or “This trade is a sure thing,” pump the brakes.
- Selective Memory: Do you recall past trades in a skewed way? Perhaps you emphasize how your analysis was right on the winners, but for your losing trades, you blame external factors.
Breaking Free: Techniques to Overcome Confirmation Bias
- Adopt a Devil’s Advocate Habit: Make it a routine part of your decision-making to argue against your trade. Ask, “What is the strongest argument that I am wrong here?”
- Use a Pre-Trade Checklist: Include questions like “Have I considered information from a variety of sources?” and “What would make me change my mind?”
- Set Objective Exit Criteria: Decide in advance what conditions would prove you wrong and stick to them.
- Keep a Trading Journal: Record not just the what and when, but also the why. Review it to identify patterns of bias.
- Practice Mindfulness: Train yourself to pause and re-center before reacting to contradictory information.
- Embrace a Culture of Challenge: Encourage yourself or your team to welcome opposing views and treat them as free risk management.
Turning Bias Awareness into Better Performance
Breaking free from confirmation bias is a game-changer for your trading performance. It will not happen overnight. But each time you seek out the uncomfortable truth instead of the comforting lie, you are training your brain to work for you, not against you.
Stay humble, stay curious, and stay disciplined.
Value truth and objectivity over the ego rush of being “right.” Over time, this mental edge compounds, helping you see the whole picture, avoid blind spots, and make better decisions.