Confirmation bias
Seeking, noticing, interpreting and remembering information in ways that support what you already believe. Once you have a view of someone, evidence for it registers and evidence against it slides past.
What drives it
Keeps beliefs stable and saves effort. Revising your view of a person can mean admitting you misjudged them, or that you treated them badly on the strength of it, so the first label is defended.
How it shows
Work
The first impression in an interview becomes the lens for the rest of it; interviewers told a candidate is introverted ask questions that can only draw introverted answers (Snyder and Swann's finding). The 'difficult' employee's every pushback is filed and their good calls are put down to luck or the team. A favoured hire's mistakes are 'learning'. Due diligence that consists of calling the referees the founder supplied.
Relationships
A partner who decided early that you are unreliable remembers the three times you were late and none of the forty you were on time. Parents keep a child's family role alive by noticing only what fits it. Going through someone's phone for the message that proves what you already suspect.
Self
Relief, even satisfaction, when someone does what you predicted ('there it is'). You can list evidence for your view of a person easily and struggle to recall any against it. You have stopped asking questions about them because you already know.
What tells it apart
Motivated reasoning: Confirmation bias works even on beliefs you don't care about; motivated reasoning is driven by a wanted conclusion and shows as harsher scrutiny of unwelcome evidence and easy acceptance of welcome evidence.
Mental filter: Mental filter is a mood-driven fixation on the negative regardless of prior belief; confirmation bias follows the existing belief, so it filters just as readily for positives about someone you like.
Anchoring: Anchoring is the pull of a first value that adjustment fails to escape; confirmation bias is active selection of what to look at, visible in the questions a person asks and the sources they consult.
A test
Write down what this person would have to do for you to change your mind, then check whether you have looked for it; if you cannot name disconfirming evidence or never sought it, the judgement is being held up by the bias.
Questions to carry
- Which of their actions this month went against the first impression, and where did those moments go in the retelling?
- If I let myself see this person differently, what would I have to admit about how I have treated them?
How strong the research is
strong
Where it comes from
Peter Wason, 1960 (2-4-6 task); Mark Snyder and William Swann, 1978 (testing hypotheses about people); Raymond Nickerson, 1998 (review)
Sources
- Amos Tversky and Daniel Kahneman, Judgment under Uncertainty: Heuristics and Biases (1974)