I tell my students that it is not the test per se that is a problem but the way it is scored and interpreted. Typologies, almost by definition will have low reliability if the trait is normally distributed. If a trait is bimodally distributed, a typology may be appropriate. However, I don't know of any evidence indicating that any of the traits measured by the MBTI are nonnormally distributed. I show the class a normal distribution and point out that, in a normal distribution, about two thirds of scores will be within one standard deviation of the mean. That means that most scores on the test are going to be fairly close to the opposite side of the distribution. So, assuming that the test has a normal standard error of measurement, the confidence interval around any individual's score is likely to contain a lot of real estate on the other side of the mean. On re-testing, there is a probability they will be classified into the other end of the typology which will produce low test-retest reliability for the typology. However, this doesn't mean the test couldn't be quite reliable if it were scored on a continuum instead of as a typology. But then I wouldn't have the joy of celebrating my INTPness. The good research that has supported the MBTI has generally treated the various subtests as continua instead of categories.
As to its theoretical validity with regard to Jung's typology (assuming adherence to Jungian theory to be a positive), Jung did not classify people into types. He encouraged finding the opposite within yourself (anima and animus). He would not tell someone: here's your type; celebrate it. He would probably encourage someone to try to find balance and harmony in his or her personality. And then there is just the faddishness of the business world in attaching itself to the next big thing that advertises itself as being based on science. Rick Dr. Rick Froman, Chair Division of Humanities and Social Sciences Box 3055 x7295 rfro...@jbu.edu http://tinyurl.com/DrFroman Proverbs 14:15 "A simple man believes anything, but a prudent man gives thought to his steps." -----Original Message----- From: tay...@sandiego.edu [mailto:tay...@sandiego.edu] Sent: Thursday, December 10, 2009 8:50 AM To: Teaching in the Psychological Sciences (TIPS) Subject: Re: [tips] MBTI Read the chapter in Scott Lilienfeld, et al's book, Science and Pseudoscience in Clinical Psychology, so as to arm yourself for a battle royale with the nuts in admin who fall for this psychobabble BS. Also you can get good info at skepdic.com My colleague and I are starting a study showing that it is pure Barnum effect. Might as well do the same but replace the MBTI with horoscopes for all the value it has. Finally, EVEN IF there was a shred of validity it would be subject to the same criticisms as for learning styles: People function best in mixed groups, not work groups limited to their own style or type. You can find evidence for that as well if you look around. Annette Annette Kujawski Taylor, Ph.D. Professor of Psychology University of San Diego 5998 Alcala Park San Diego, CA 92110 619-260-4006 tay...@sandiego.edu ---- Original message ---- >Date: Thu, 10 Dec 2009 08:58:37 -0500 >From: "Bourgeois, Dr. Martin" <mbour...@fgcu.edu> >Subject: [tips] MBTI >To: "Teaching in the Psychological Sciences (TIPS)" <tips@acsun.frostburg.edu> > >I just received the following email from my university, and before responding, >I thought I'd get some other opinions. Here's the email: > >Based upon Carl Jung’s research on psychological types, the Myers-Briggs Type >Indicator (MBTI) was developed by Isabel Briggs Myers and her mother Katharine >Cook Briggs, and has become the most widely trusted personality inventory in >the United States and throughout the world. Participants will complete the >MBTI inventory, learn about personality types, and receive their individual >personality profiles during this series. In Session #1, participants will >complete the MBTI inventory, with program and results covered in Session #2. > > >My understanding is that the MBTI is held in low regard by personality >psychologists, and has shown little validity. Any thoughts? >--- >To make changes to your subscription contact: > >Bill Southerly (bsouthe...@frostburg.edu) --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu) --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
