What is... psychology series

What is… a cognitive bias

list of common cognitive biases

In this series, I dig a little deeper into the meaning of psychology-related terms.  This week’s term is cognitive bias.

Do you think you’re biased?  Well, your brain certainly is.  Cognitive biases are some of the shortcuts your brain takes to make tasks easier and more automatic.  Sometimes that’s helpful, but often it’s not, especially when we’re unaware of it.

Here are some examples:

  • ambiguity effect: we’re naturally inclined to go for the “sure thing” rather than something with an uncertain outcome, even when the result would be better if the uncertain outcome occurred
  • anthropomorphism: this is when we attribute human characteristics to non-human objects, such as my belief that my guinea pigs love their mama (i.e. me)
  • belief bias: the strength of a logical argument is evaluated based on the subjective believability of the conclusion rather than on the strength of the arguments that led to the conclusion
  • Ben Franklin effect: if you’ve previously done someone a favour, you’re more likely to do them another favour than if it was them who had originally done a favour for you
  • bias blind spot: we tend to believe that we are less biased than other people are
  • confirmation bias: we tend to both seek out and focus on information that confirms what we already believe, and ignore information that goes against our beliefs
  • curse of knowledge: this is the assumption that other people have the same level of background knowledge as you do; I tend to get caught up in this, so I ‘ve never been very good with nursing students because I always assume they should have more knowledge than they actually do
  • framing effect: receiving the same information is evaluated differently depending on how it’s framed
  • gambler’s fallacy: believing that because you’ve had half an hour of losing at a particular slot machine, that means the machine is due to pay out imminently
  • hindsight bias: an outcome seems like it should have been obviously predictable after it’s already happened
  • hyperbolic discounting: the preference for a smaller short-term gain over a larger but delayed gain
  • negativity bias: we’re more likely to notice and remember things that are negative compared to things that are positive
  • observer-expectancy effect: expecting a certain outcome causes the observer to unconsciously do things to influence the outcome; clinical research trials are often designed to be double-blinded to account for this
  • post-purchase rationalization: even if you spent far too much money on something, you’ll likely try to convince yourself afterwards that it was totally worth it
  • reactive devaluation: if someone you don’t like makes a suggestion, you’ll tend to automatically assume it’s a bad suggestion
  • rhyme as reason effect: this seems utterly bizarre, but Wikipedia gives this example from O.J. Simpson’s trial: “If the gloves don’t fit, then you must acquit.”
  • sunk cost fallacy: the tendency to think that you should stick with something because you’ve already put a lot of time and effort in,
  • unit bias: even if you’re only hungry enough to need a small plate of food, if given a large plate you’ll judge that full plate as being the appropriate amount

There are many, many more examples.  Some of them have a greater degree of voluntariness, such as the ostrich effect (i.e. sticking one’s head in the sand to ignore something bad happening), while others we likely wouldn’t realize if they weren’t pointed out to us.  It’s a good reminder that the ways that we perceive the world around us are often not an objectively accurate representation.


You can find the rest of my What Is series here.

Source: Wikipedia: List of cognitive biases



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25 thoughts on “What is… a cognitive bias”

  1. Wow, I could relate to so many of these!! Like, check, check, check, check, check. What a fascinating list! Oh, but I’m sure the guinea pigs love you to death!!

  2. Wow! I’ve heard of some of these but certainly didn’t realise there are so many typical patterns influencing thought, judgement and action. Great post x

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