The cognitive phenomenon of "anchoring" dramatically leads human judgments astray, psychologists confirm.
People's beliefs and judgments are very often anchored on incomplete, deficient and sketchy information that forms the basis of a lifelong mindset, impervious to persuasion and adjustment. The resulting cognitive bias is pervasive; it vigorously resists any subsequent interpretation of information that might alter the anchored conviction.
Such opinions, judgments and convictions come to be set in stone, generating potential errors in accurate mental analyses. It is a lapse in the "normative" process that regulates opinions with regard to the appropriateness of social behaviours.
"I am not very optimistic about people's abilities to change the way they think," concluded Daniel Kahneman, a psychologist at Princeton University. "(Our) thinking becomes anchored...(and) we are not often aware of how little information (it is based on)."
"Anchoring immunizes beliefs against persuasion," concludes researcher Carnot Nelson.
According to Noel Brewer at the University of North Carolina, Gretchen Chapman at Rutgers University and their colleagues, "decades of research shows that judgments typically and robustly assimilate towards irrelevant anchors."
The anchoring paradigm invites significant judgment errors, because basic anchored beliefs are not adjusted by any infusion of contradictory information, which is simply ignored.
"Anchors provided by an external source do not activate processes of adjustment," confirmed Nicolas Epley at Harvard University and Thomas Gilovitch at Cornell University.
"Judgment biases are thought to be the product of insufficient adjustment from an initial anchor value," they reported.
It is as if people are mentally blind to supplementary information that might conflict with a deeply held anchored view, even though that anchor value is known to be incorrect.
Some self-generated anchors, such as those related to self-perception, even though erroneous, are rarely altered. They often lead to unwarranted overconfidence, Kahneman suggested.
The "everybody loves me" delusion is a fairly typical self-generated anchor that promotes a self-perception that exceeds how others actually value us, according to Gregory Preuse and colleagues at Ohio University.
Anchoring is pervasive, but sad people are comparatively most vulnerable, according to researchers Galen Bodenhauser, Shira Gabriel and Megan Lineberger at Northwestern University.
Normative beliefs, those pertaining to social behavioural norms, generate specific actions influenced by anchors, according to Jessica Nolan at the University of Scranton.
Brewer and his colleagues report anchoring biases have huge potential implications with undervalued complex underpinnings.
"Referendums, especially yes/no referendums, are highly vulnerable to anchoring," concluded Donald Green at Yale University, Karen Jacowitz at the University of California and their colleagues.
Research at the National Institutes of Health in Maryland confirm that people fail to adjust their anchored misconceptions even in the face of risk warnings made by a health-care provider, resulting in "misperception of disease risk."
Researchers are not sure why the human mind regularly bases lifelong perceptions on fragmentary, incomplete and sometimes incorrect information to which people are often exposed in childhood or adolescence, or which are self-generated as a result of flawed analyses.
"(People don't) wait for (additional ) information but form an impression on the basis of (anchored) bits of information," Kahneman explained.
Anchoring causes people to focus on plausible explanations based a few core shreds of information, and to exclude any input that might contradict the anchored viewpoint, researchers propose.
Robert Alison is a zoologist and
freelance writer in Victoria, B.C.