Confirmation bias
Confirmation bias is the tendency to notice and value information that supports what you already believe and to ignore what contradicts it. In trading it keeps you in bad trades.
How it works
Once you are in a position or attached to a coin, your brain looks for support: you read only bullish posts, see only signals in your favour on the chart, and dismiss counterarguments as FUD. This is not stupidity but a normal feature of human thinking that everyone has.
In trading the consequences are concrete: you do not exit when the idea has failed, you move your stop, you add to a loser. Analysis turns into searching for excuses for a decision you have already made.
It helps to write down in advance what would prove you wrong (your invalidation) and to deliberately look for the best argument against your trade. Comparing in your journal what you expected with what actually happened also helps.
You bought an altcoin and follow ten channels that praise it. Price breaks a key level down, but you read a post saying it is just shaking out weak hands and keep holding. If you had written before entering that you would close on a hold below $1.20, the rules would decide, not your mood.
The main mistake is doing your analysis after entering a trade and calling it a check. Once you are in, you want one specific answer. Do the analysis and write your invalidation before entry, and afterwards only check that condition instead of hunting for new reasons to hold.
Questions and answers
What is confirmation bias in simple terms?
It is believing what agrees with your opinion and overlooking what goes against it.
How does confirmation bias hurt traders?
It makes you hold losing trades and look for excuses instead of admitting a mistake and exiting at your stop.
How do you avoid confirmation bias in trading?
Write down what would prove your idea wrong before you enter. Look for the strongest case against your trade and compare expectations with results in your journal.
Related terms
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Updated: 2026-10-19