11. Confirmation Bias
What Is Confirmation Bias?
Confirmation bias is the tendency to seek out and attend to information that affirms one’s pre-existing beliefs and expectations while avoiding or ignoring information that contradicts them.
The previous example illustrates how biases, including confirmation bias, come into play in heuristic reasoning, which is fast and, by definition, only uses a subset of the available information (making it more likely to be susceptible to biases and errors). It is important to recognize, however, that biases can just as easily exist in effortful/systematic/analytical thinking, especially confirmation bias.
Example: Presentation
Imagine you are preparing a presentation at your workplace to suggest a specific strategy for your team to implement. You want to show everyone that this strategy is worthwhile and effective, so you do a lot of research to find evidence of its effectiveness. You spend a lot of time and effort on this, and your presentation is very successful. The team decides to adopt the strategy.
Well done — you are on your way to that promotion! But what is the problem here? The problem is that, in your research, you only looked for evidence that supported your idea. You did not look for evidence that discredited it.
Confirmation Bias in Scientific Research
You can see this routinely in scientific research. In the scientific method, you come up with a theory and then propose specific hypotheses to test that theory. The idea behind “testing” is you try to disprove your theory. However, we mostly see people finding ways to support their theories, or, at best, invalidate someone else’s competing theory — which is why research rivalry is very important. 😊
Repeatedly coming up with hypotheses that corroborate your theory — with no hypotheses that oppose it — is a clear example of confirmation bias in analytical thinking (e.g. Mynatt et al., 1977). This bias stems from how we generally seek consistency among our internal states (beliefs, thoughts, and emotions) as well as between our internal states and our behaviour (e.g. the research we engage in).
Thus, a prominent cognitive explanation of confirmation bias is Festinger’s (1957) concept of cognitive dissonance (D’Alessio & Allen, 2002).
What Is Cognitive Dissonance?
If we engage in research that knocks down our own ideas or if we truthfully entertain conceptions directly opposing our own, it will likely cause cognitive dissonance.
Cognitive dissonance is the feeling of psychological unease and discomfort when we try to hold contradictory beliefs or when our beliefs and actions are inconsistent with each other. Adopting confirmation bias avoids this unpleasant state.
The mechanism underlying confirmation bias has even been studied at the neural level (Kappes et al., 2020).
