Confirmation Effect
Unhappy with his four-year-old’s new preschool, Seth decides to ask other local parents for their opinions on an online forum. As he reads their responses, he focuses on the negative stories, discounting or ignoring positive responses. Seth’s behavior in this situation is influenced by confirmation bias, or the widespread tendency to seek out information that confirms one’s pre-existing beliefs.
Why it’s relevant to parent engagement:
It can be difficult to change complex, intentional behaviors without first changing corresponding beliefs. Consequently, many interventions targeting parents aim to shift parental beliefs, a process frequently hampered by confirmation bias. Parents’ beliefs are often deep-seated and persistent. As a result, some parents may be almost completely immune to objective evidence, expert advice, or real-world anecdotes that do not align with their pre-existing worldviews.
Evidence:
Confirmation bias has been observed in a wide variety of laboratory settings. For instance, undergraduates who read two equivalent studies providing evidence for and against the death penalty, respectively, rated the study that matched their pre-existing beliefs as more methodologically sound. Furthermore, their pre-existing opinions about capital punishment grew more extreme after they read the two studies.
In a classic experiment, participants evaluated the future prospects of a hypothetical child based on a short video of her answering questions. Half the participants had been told that the child was from a low-income family, while the other half believed she belonged to a well-off family. The two groups formed disparate beliefs about the girl’s prospects, finding confirmatory evidence for these beliefs in the same video.
Outside the lab, physicians can fall victim to confirmation bias, allowing pre-existing assumptions to cloud their clinical judgment. For example, physicians provided with details about a patient, even if those details are inaccurate, are more likely to make an incorrect diagnosis or misinterpret test results.
Parents who attribute malicious motivations to their children’s misbehavior tend to fixate on interactions that confirm these beliefs. These parents report more frequent and intense instances of misbehavior than parents who do not view their children as “bad kids.”
Doctors’ and public health agencies’ attempts to counter parents’ refusal to vaccinate their children have been hampered by confirmation bias. Parents who oppose vaccines are surprisingly resistant to information that contradicts these beliefs, from factual evidence to reassurance from medical authorities.
Unhappy with his four-year-old’s new preschool, Seth decides to ask other local parents for their opinions on an online forum. As he reads their responses, he focuses on the negative stories, discounting or ignoring positive responses. Seth’s behavior in this situation is influenced by confirmation bias, or the widespread tendency to seek out information that confirms one’s pre-existing beliefs.
Why it’s relevant to parent engagement:
It can be difficult to change complex, intentional behaviors without first changing corresponding beliefs. Consequently, many interventions targeting parents aim to shift parental beliefs, a process frequently hampered by confirmation bias. Parents’ beliefs are often deep-seated and persistent. As a result, some parents may be almost completely immune to objective evidence, expert advice, or real-world anecdotes that do not align with their pre-existing worldviews.
Evidence:
Confirmation bias has been observed in a wide variety of laboratory settings. For instance, undergraduates who read two equivalent studies providing evidence for and against the death penalty, respectively, rated the study that matched their pre-existing beliefs as more methodologically sound. Furthermore, their pre-existing opinions about capital punishment grew more extreme after they read the two studies.
1
Lord, C. G., Ross, L., & Lepper, M. R. (1979). Biased assimilation and attitude polarization: The effects of prior theories on subsequently considered evidence. Journal of Personality and Social Psychology, 37(11), 2098.
Participants in an analogous experiment focused on nuclear power had similar reactions, favoring evidence that confirmed their beliefs and increasing confidence in their pre-existing opinions.
2
Plous, S. (1991). Biases in the assimilation of technological breakdowns: Do accidents make us safer? Journal of Applied Social Psychology, 21(13), 1058-1082.
In a classic experiment, participants evaluated the future prospects of a hypothetical child based on a short video of her answering questions. Half the participants had been told that the child was from a low-income family, while the other half believed she belonged to a well-off family. The two groups formed disparate beliefs about the girl’s prospects, finding confirmatory evidence for these beliefs in the same video.
3
Darley, J. M., & Gross, P. H. (1983). A hypothesis-confirming bias in labeling effects. Journal of Personality and Social Psychology, 44(1), 20.
Outside the lab, physicians can fall victim to confirmation bias, allowing pre-existing assumptions to cloud their clinical judgment. For example, physicians provided with details about a patient, even if those details are inaccurate, are more likely to make an incorrect diagnosis or misinterpret test results.
4,
Flach, S. D., Canaris, G. J., Tape, T. G., Huntley, K. M., & Wigton, R. S. (2002). The effects of proficiency and bias on residents’ interpretation of the microscopic urinalysis. Medical Decision Making, 22(4), 318-325.
5
Tschan, F., Semmer, N. K., Gurtner, A., Bizzari, L., Spychiger, M., Breuer, M., & Marsch, S. U. (2009). Explicit reasoning, confirmation bias, and illusory transactive memory: A simulation study of group medical decision making. Small Group Research, 40(3), 271-300.
Similarly, teachers who are led to presume that certain students are more gifted than others tend to find confirmation of these false beliefs in subsequent interactions with these students.
6
Rosenthal, R., & Jacobson, L. (1968). Pygmalion in the classroom. The Urban Review, 3(1), 16-20.
Parents who attribute malicious motivations to their children’s misbehavior tend to fixate on interactions that confirm these beliefs. These parents report more frequent and intense instances of misbehavior than parents who do not view their children as “bad kids.”
7
Nelson, J. A., O’Brien, M., Calkins, S. D., & Keane, S. P. (2013). Mothers’ and fathers’ negative responsibility attributions and perceptions of children’s problem behavior. Personal Relationships, 20(4), 719-727.
Doctors’ and public health agencies’ attempts to counter parents’ refusal to vaccinate their children have been hampered by confirmation bias. Parents who oppose vaccines are surprisingly resistant to information that contradicts these beliefs, from factual evidence to reassurance from medical authorities.
8
Horne, Z., Powell, D., Hummel, J. E., & Holyoak, K. J. (2015). Countering antivaccination attitudes. Proceedings of the National Academy of Sciences, 112(33), 10321-10324.