Bias

Bias is a term used to describe a tendency or preference towards a particular perspective, ideology or result, especially when the tendency interferes with the ability to be impartial, unprejudiced, or objective.

Humans are subject to scores of specific, predictable error patterns that are likely to make your beliefs… well… not the sorts of things you'd like to bet your future on. The biases and heuristics research program within cognitive psychology gathered solid documentation of many of these specific error patterns – many reasons why you can expect particular sorts of errors in your current beliefs. Take this research seriously, and you'll never think the same way again.

Some starting-points:

• Daniel Kahneman's Nobel prize acceptance speech, where he summarizes the work for which he won the prize;
• Wikipedia:List of cognitive biases;
• Kahneman et al's three edited volumes of research on heuristics and biases (this is the best solid source, but requires obtaining hard-copy books, and is slower reading);
• Cialdini's book Influence: Science and Practice (at once contentful and full of engaging anecdotes and cartoons, but, again, requires actually obtaining a book);
• Eliezer's introductory book chapter Cognitive biases affecting judgment of existential risks (available online).
• Psychology Wiki's list of Cognitive Biases

See Also

• Statistical Bias

References

Overcoming Bias Articles

• What exactly is bias? by Nick Bostrom
• To the barricades! Against ... what exactly? by Robin Hanson
• ... What's a bias, again? by Eliezer Yudkowsky
• Are The Big Four Econ Errors Biases? by Robin Hanson
• In[]cautious defense of bias by Paul Gowder
• Seen vs. Unseen Biases by Robin Hanson
• Knowing About Biases Can Hurt People — Knowing about common biases doesn't help you obtain truth if you only use this knowledge to attack beliefs you don't like.
• Scope Insensitivity — The human brain can't represent large quantities: an environmental measure that will save 200,000 birds doesn't conjure anywhere near a hundred times the emotional impact and willingness-to-pay of a measure that would save 2,000 birds, even though in fact the former measure is two orders of magnitude more effective. (See also further commentary in One Life Against the World, and the terrible dilemma of Torture vs. Dust Specks)
• Correspondence Bias, also known as the fundamental attribution error, refers to the tendency to attribute the behavior of others to intrinsic dispositions, while excusing one's own behavior as the result of circumstance.
• Confirmation bias, or Positive Bias is the tendency to look for evidence that confirms a hypothesis, rather than disconfirming evidence.
• Hindsight Bias describes the tendency to seem much more likely in hindsight than could have been predicted beforehand.
• Planning Fallacy — We tend to plan envisioning that everything will go as expected. Even assuming that such an estimate is accurate conditional on everything going as expected, things will not go as expected. As a result, we routinely see outcomes worse then the ex ante worst case scenario.
• Conjunction Fallacy — Elementary probability theory tells us that the probability of one thing (we write P(A)) is necessarily greater than or equal to the conjunction of that thing and another thing (write P(A&B)). However, in the psychology lab, subjects' judgments do not conform to this rule. This is not an isolated artifact of a particular study design. Debiasing won't be as simple as practicing specific questions, it requires certain general habits of thought.
• We Change Our Minds Less Often Than We Think — we all change our minds occasionally, but we don't constantly, honestly reevaluate every decision and course of action. Once you think you believe something, the chances are good that you already do, for better or worse.
• Priming and Contamination, Never Leave Your Room, and Cached Selves — Even slight exposure to a stimulus is enough to change the outcome of a decision or estimate.
• Do We Believe Everything We're Told? — Some experiments on priming suggest that mere exposure to a view is enough to get one to passively accept it, at least until it is specifically rejected.
• Illusion of Transparency — Everyone knows what their own words mean, but experiments have confirmed that we systematically overestimate how much sense we are making to others.
• Self-Anchoring — Related to contamination and the illusion of transparancy, we "anchor" on our own experience and underadjust when trying to understand others.
• Affect Heuristic — Positive and negative emotional impressions exert a greater effect on many decisions than does rational analysis.
• Evaluability — It's difficult for humans to evaluate an option except in comparison to other options. Poor decisions result when a poor category for comparison is used. Includes an application for cheap gift-shopping.
• Unbounded Scales, Huge Jury Awards, and Futurism — Without a metric for comparison, estimates of, e.g., what sorts of punative damages should be awarded, or when some future advance will happen, vary widely simply due to the lack of a scale.
• The Halo Effect — Positive qualities seem to correlate with each other, whether or not they actually do.
• Asch's Conformity Experiment — The unanimous agreement of surrounding others can make subjects disbelieve (or at least, fail to report) what's right before their eyes. The addition of just one dissenter is enough to dramatically reduce the rates of improper conformity.
• The Allais Paradox (and subsequent followups) — Offered choices between gambles, people make decision-theoretically inconsistent decisions.