Featured Research

from universities, journals, and other organizations

People are overly confident in their own knowledge, despite errors

Date:
June 10, 2013
Source:
Association for Psychological Science
Summary:
Overprecision -- excessive confidence in the accuracy of our beliefs -- can have profound consequences, inflating investors' valuation of their investments, leading physicians to gravitate too quickly to a diagnosis, even making people intolerant of dissenting views. Now, new research confirms that overprecision is a common and robust form of overconfidence driven, at least in part, by excessive certainty in the accuracy of our judgments.

New research confirms that overprecision is a common and robust form of overconfidence driven, at least in part, by excessive certainty in the accuracy of our judgments.
Credit: pressmaster / Fotolia

Overprecision -- excessive confidence in the accuracy of our beliefs -- can have profound consequences, inflating investors' valuation of their investments, leading physicians to gravitate too quickly to a diagnosis, even making people intolerant of dissenting views. Now, new research confirms that overprecision is a common and robust form of overconfidence driven, at least in part, by excessive certainty in the accuracy of our judgments.

Related Articles


The research, conducted by researchers Albert Mannes of The Wharton School of the University of Pennsylvania and Don Moore of the Haas School of Business at the University of California, Berkeley, revealed that the more confident participants were about their estimates of an uncertain quantity, the less they adjusted their estimates in response to feedback about their accuracy and to the costs of being wrong.

"The findings suggest that people are too confident in what they know and underestimate what they don't know," says Mannes.

The new findings are published in Psychological Science, a journal of the Association for Psychological Science.

Research investigating overprecision typically involves asking people to come up with a 90% confidence interval around a numerical estimate -- such as the length of the Nile River -- but this doesn't always faithfully reflect the judgments we have to make in everyday life. We know, for example, that arriving 15 minutes late for a business meeting is not the same as arriving 15 minutes early, and that we ought to err on the side of arriving early.

Mannes and Moore designed three studies to account for the asymmetric nature of many everyday judgments. Participants estimated the local high temperature on randomly selected days and their accuracy was rewarded in the form of lottery tickets toward a prize. For some trials, they earned tickets if their estimates were correct or close to the actual temperature (above or below); in other trials, they earned tickets for correct guesses or overestimates; and in some trials they earned tickets for correct guesses or underestimates.

The results showed that participants adjusted their estimates in the direction of the anticipated payoff after receiving feedback about their accuracy, just as Mannes and Moore expected.

But they didn't adjust their estimates as much as they should have given their actual knowledge of local temperatures, suggesting that they were overly confident in their own powers of estimation.

Only when the researchers provided exaggerated feedback -- in which errors were inflated by 2.5 times -- were the researchers able to counteract participants' tendency towards overprecision.

The new findings, which show that overprecision is a common and robust phenomenon, urge caution:

"People frequently cut things too close -- arriving late, missing planes, bouncing checks, or falling off one of the many 'cliffs' that present themselves in daily life," observe Mannes and Moore.

"These studies tell us that you shouldn't be too certain about what's going to happen, especially when being wrong could be dangerous. You should plan to protect yourself in case you aren't as right as you think you are."


Story Source:

The above story is based on materials provided by Association for Psychological Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. E. Mannes, D. A. Moore. A Behavioral Demonstration of Overconfidence in Judgment. Psychological Science, 2013; DOI: 10.1177/0956797612470700

Cite This Page:

Association for Psychological Science. "People are overly confident in their own knowledge, despite errors." ScienceDaily. ScienceDaily, 10 June 2013. <www.sciencedaily.com/releases/2013/06/130610113012.htm>.
Association for Psychological Science. (2013, June 10). People are overly confident in their own knowledge, despite errors. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2013/06/130610113012.htm
Association for Psychological Science. "People are overly confident in their own knowledge, despite errors." ScienceDaily. www.sciencedaily.com/releases/2013/06/130610113012.htm (accessed October 30, 2014).

Share This



More Mind & Brain News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Studying Effects of Music on Dementia Patients

Studying Effects of Music on Dementia Patients

AP (Oct. 30, 2014) The University of Wisconsin-Milwaukee is studying the popular Music and Memory program to see if music, which helps improve the mood of Alzheimer's patients, can also reduce the use of prescription drugs for those suffering from dementia. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Techy Tots Are Forefront of London's Baby Show

Techy Tots Are Forefront of London's Baby Show

AP (Oct. 28, 2014) Moms and Dads get a more hands-on approach to parenting with tech-centric products for raising their little ones. (Oct. 28) Video provided by AP
Powered by NewsLook.com
Cocoa Could Be As Good For Memory As It Is For A Sweet Tooth

Cocoa Could Be As Good For Memory As It Is For A Sweet Tooth

Newsy (Oct. 27, 2014) Researchers have come up with another reason why dark chocolate is good for your health. A substance in the treat can reportedly help with memory. Video provided by Newsy
Powered by NewsLook.com
Five-Year-Olds Learn Coding as Britain Eyes Digital Future

Five-Year-Olds Learn Coding as Britain Eyes Digital Future

AFP (Oct. 27, 2014) Coding has become compulsory for children as young as five in schools across the UK. Making it the first major world economy to overhaul its IT teaching and put programming at its core. Duration: 02:19 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins