Confirmation Bias is regarded by Gary Dayton and Mark Douglas as one of the most common and deceptive psychological traps for traders.
The core of this bias lies in the asymmetric processing of information: traders tend to observe the market through a "filter lens"—automatically capturing and amplifying information that supports their positions while unconsciously screening out, distorting, or downplaying warning signals that contradict their viewpoints.
──────────────────
1. Psychological Mechanism: To feel good and to defend against pain
The two authors agree that confirmation bias is not simply a laziness of thought, but a deep-seated psychological defense mechanism.
Seeking Psychological Reinforcement (Dopamine Driven):
Gary Dayton points out that humans have a primal urge to prove they are 'right'. When we find evidence supporting our trading hypotheses, our brains produce a form of psychological reinforcement (Reward), making us feel confident and pleased.Mechanism: To maintain this 'feel-good' state, intuitive thinking (System 1) instinctively drives us to seek more of the same evidence, forming a closed 'echo chamber'.
Pain Avoidance and Cognitive Distortion (Fear Driven):
Mark Douglas approaches this from the perspective of **'fear'**. He points out that fear limits our bandwidth for perceiving environmental information. If we fear losses or admitting mistakes, our subconscious will automatically block out all 'threatening information' that shows the market is unfavorable to us.Mechanism: Douglas refers to this as 'cognitive distortion' — to avoid the emotional pain caused by unmet expectations, we distort our perception of reality, forcing the external environment to conform to our internal expectations.
2. Pathological Manifestations in Trading
Confirmation bias in technical analysis and position management typically manifests as two highly destructive behavioral patterns:
A. Technical Trap: Multicollinearity
Dayton specifically points out a commonly overlooked technical blind spot. Traders seeking 'security' will overlay multiple indicators that are essentially the same on their charts (e.g., using RSI, KDJ, and Stochastics simultaneously).
Phenomenon: Because these indicators are based on similar mathematical principles, they often emit the same signals simultaneously.
Consequence: Influenced by confirmation bias, traders misinterpret this 'tautology' as 'multiple confirmations', leading to overconfidence and heavy positions. They believe they have seen the truth, but in reality, they have only viewed the same data in three different ways.
B. Decision Trap: Bag-holding
Douglas describes a classic scenario: When an account shows floating losses, fear is activated.
Phenomenon: To avoid stop-losses (admitting failure), traders scan the market like a radar, desperately searching for any signs that support a rebound (like a trivial piece of good news, or a slight divergence on the 1-minute chart).
Consequence: They assign excessive weight to these minor pieces of information while overlooking significant breakdowns on the weekly level. This is a form of **'selective blindness'**.
──────────────────
3. Fundamental Issue: Rejecting 'Falsification'
The root of confirmation bias lies in the trader's refusal to acknowledge that they could be wrong.
Equating belief with truth:
Douglas emphasizes that novice traders often see their market analysis as 'absolute truth'. Once caught in this mindset, any contrary information (such as a price drop) will be seen as an attack on 'truth' (i.e., self-worth), triggering psychological defenses.Viewing 'Falsification' as a Threat:
Dayton cites Soros's view that the core ability of rational trading is **'actively seeking information that overturns one's own hypotheses'**. However, under the influence of confirmation bias, searching for counterexamples is viewed as a psychological threat, implying one must face the painful reality of 'I am wrong'.
──────────────────
4. Solution: Shift from 'Seeking Confirmation' to 'Seeking Falsification'
To break this cycle of self-deception, deliberate, counterintuitive cognitive interventions (System 2 involvement) must be undertaken:
Ⅰ. Enforce 'Falsification Questions'
Dayton suggests that before placing an order or when feeling uneasy about a position, force yourself to answer reverse questions:
'If I were the short seller in this market, what evidence would I seek?'
'What objective reasons indicate that this trade has failed?'
By actively seeking opposing signals, force a balance against the brain's craving for confirming information.
Ⅱ. Optimize Technical Indicator Library
On a technical level, Dayton suggests conducting **'de-correlation'** processing. Ensure that the indicators you use measure different dimensions of the market (e.g., one looks at trends, one looks at momentum, one looks at volume), rather than piling up similar indicators to create a false sense of security.
Ⅲ. Embrace Probabilistic Thinking
Douglas's ultimate advice is: Give up proving that you are right.
When you truly accept that 'anything can happen', you sever the link between self-esteem and trading outcomes. Once you no longer need to maintain the illusion of 'I am right', the filter of confirmation bias will naturally shatter, and you will clearly see the exit signals that the market issues for the first time.
──────────────────
Conclusion
What we often seek in the market is not the truth, but comfort.
Confirmation bias is an expensive pair of tinted glasses. Taking them off may feel glaring and painful, but it is the necessary path to becoming a professional trader.
Remember: The market is not responsible for validating your views; it is only responsible for validating your rules.