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Critical Thinking About Sources

What is Bias?

From Cambridge Dictionary of Sociology:
Bias refers to those aspects of the social research process that may skew the findings in some way. The main identified sources of bias concern the researcher or informant, the measurement instruments or methods, and the sampling procedures. Biased measures fail to do a good job of measuring the things they are purported to measure and therefore lack validity. Biased samples are not representative of the relevant population or set of cases they are meant to reflect.

There are hundreds of different types of bias that have been identified. These different categories of bias have multiple bias examples within them. Some commonly recognized types of bias are:

  • Cognitive bias
  • Prejudices
  • Contextual bias
  • Unconscious or implicit bias
  • Statistical bias

Cognitive Bias

What is Cognitive Bias?

A cognitive bias is a systematic pattern of deviation from norm or rationality in judgment. Individuals create their own "subjective reality" from their perception of the input. An individual's construction of reality, not the objective input, may dictate their behavior in the world.

20 Cognitive Biases that screw up your decisions - from Business Insider

  1. Anchoring bias: People are over-reliant on the first piece of information they hear. In a salary negotiation, whoever makes the first offer establishes a range of reasonable possibilities in each person's mind.
  2. Availability heuristic: People overestimate the importance of the information available to them. A person might argue that smoking is not unhealthy because they know someone who lived to 100 and smoked three packs a day.
  3. Bandwagon Effect: The probability of one person adopting a belief increases based on the number of people who hold that belief. This is a powerful form of groupthink and is reason why meetings are often unproductive.
  4. Blind-spot bias: Failing to recognize your own cognitive bias is a bias in itself. People notice cognitive and motivational biases much more in other than in themselves.
  5. Choice-supportive bias: When you choose something, you tend to feel positive about it, even if that choice has flaws. Like how you think your dog is awesome - even if it bites people every once in a while.
  6. Clustering illusion: This is the tendency to see patterns in random events. It is key to various gambling fallacies, like the idea that red is more or less likely to turn up on a roulette table after a string of reds.
  7. Confirmation bias: We tend to listen only to information that confirms our preconceptions - one of the many reasons it's so hard to have an intelligent conversation about climate change.
  8. Conservatism bias: Where people favor prior evidence over new evidence or information that has emerged. People were slow to accept that the earth was round because they maintained their earlier understanding that the planet was flat.
  9. Information bias: The tendency to seek information when it does not affect action. More information is not always better. With less information, people can often make more accurate predictions.
  10. Ostrich effect: The decision to ignore dangerous or negative information by "burying" one's head in the sand, like an ostrich. Research suggests that investors check the value of their holdings significantly less often during bad markets.
  11. Outcome bias: Judging a decision based on the outcome - rather than how exactly the decision was made in the moment. Just because you won a lot in Vegas doesn't mean gambling your money was a smart decision.
  12. Overconfidence: Some of us are too confident about our abilities, and this causes us to take greater risks in our daily lives. Experts are more prone to this bias than laypeople, since they are more convinced that they are right.
  13. Placebo effect: When simply believing that something will have a certain effect on you causes it to have that effect. In medicine, people given fake pills often experience the same physiological effects as people given the real thing.
  14. Pro-innovation bias: When a proponent of an innovation tends to overvalue its usefulness and undervalue its limitations. Sound familiar, Silicon Valley?
  15. Recency: The tendency to weight the latest information more heavily than older data. Investors often think the market will always look the way it looks today and make unwise decisions.
  16. Salience: Our tendency to focus on the most easily recognizable features of a person or concept. When you think about dying, you might worry about being mauled by a lion, as opposed to what is statistically more likely, like dying in a car accident.
  17. Selective perception: Allowing our expectations to influence how we perceive the world. An experiment involving a football game between students from two universities showed that one team saw the opposing team commit more infractions.
  18. Stereotyping: Expecting a group or person to have certain qualities without having real information about the person. It allows us to quickly identify strangers as friends or enemies, but people tend to overuse and abuse it.
  19. Survivorship bias: An error that comes from focusing only on surviving examples, causing us to misjudge a situation. For instance, we might think that being an entrepreneur is easy because we haven't heard of all those who failed.
  20. Zero-risk bias: Sociologists have found that we love certainty - even if it's counterproductive. Eliminating risk entirely means there is no chance of harm being caused.

20 types of cognitive bias chart by business insider