Cognitive biases are systematic patterns of deviation from norm or rationality in judgment, originating from the brain's need to simplify information processing. First cataloged comprehensively by Daniel Kahneman and Amos Tversky in the 1970s, these mental shortcuts affect personal decisions, professional judgments, and social interactions. While biases evolved to help humans make quick decisions under uncertainty, they often lead to predictable errors in thinking—from overestimating our abilities to misjudging probabilities. Understanding these biases is the first step toward debiasing: once you recognize that your judgment naturally skews in specific directions, you can implement strategies to correct course before committing to flawed decisions.
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Table 1: Memory and Information Processing Biases
Memory shapes and distorts more than it records—our brains actively reconstruct the past and filter present information through existing beliefs. These biases explain why eyewitness testimony is unreliable, why confirming facts stick in memory better than disconfirming ones, and why the internet age has subtly reshaped what we even bother to remember.
| Bias | Example | Description | |
|---|---|---|---|
Searching only for articles that support your political view | Tendency to favor information that confirms preexisting beliefs while ignoring or dismissing contradictory evidence. | ||
Overestimating plane crash risk after seeing news coverage | Judging likelihood of events based on how easily examples come to mind rather than actual statistical probability. | ||
First salary offer of $60K influences all counteroffers | Relying too heavily on the first piece of information encountered when making decisions. | ||
Believing vitamin C prevents colds after hearing it repeated | • Tendency to judge repeated statements as true regardless of actual accuracy • repetition creates a feeling of familiarity mistaken for truth | ||
Employee evaluation focuses on last month only | Tendency to remember and overweight the most recent information when making judgments. | ||
"I knew it all along" after election results | Believing past events were more predictable than they actually were after outcomes are known. | ||
First impression at interview dominates evaluation | • Tendency to remember first items in a sequence more vividly • shapes lasting impressions disproportionate to later information | ||
Sports fan only notices referee calls against their team | Perceiving stimuli that confirm existing biases while filtering out contradictory information. | ||
Looking up the same word definition three times because it doesn't stick | • Tendency to forget information that is easily searchable online • we offload memory to external search rather than encoding it internally | ||
Believing your lucky shirt influences your team's win rate | Perceiving a relationship between two unrelated variables because co-occurrences are more memorable than non-occurrences. | ||
Seeing patterns in random stock price movements | Perceiving patterns in random data when none actually exist. | ||
"That vacation was amazing" despite remembering the delays | • Recalling the past more positively than it was actually experienced • nostalgia inflates the emotional quality of past events |