Limitations of the Big 5
Friday, February 12, 2010 at 7:50AM I talk a lot about the Big 5 personality factors, and how useful they are. So now it is time to discuss the problems with the Big 5. As in so many things, I am indebted to Steve Sailer for bringing these up first.
Problem 1 is cheating. A person who knows how these traits work can present any personality they wish on a personality test, which is really more of a self-guided assessment. This limits their use for school and work purposes. I have to watch for this myself when I take the tests now, because I know what each question is getting at. In some ways, the best assessment is the first one.
Problem 2 is cross-cultural validity. Unlike IQ tests, where the psychometricians have long since figured out how to take cultural-bias out of tests, Big 5 tests ask about behavioral responses, which vary a lot between different groups. Big 5 tests seem to not even work very well comparing different states to each other in the USA, much less to other countries. This is less of a problem if the group is self-selected, like med students say, then the comparisons are likely to be much more fruitful. I think this is one reason why the Big 5 is so much less directive about career than the MBTI has been. There just aren't meaningful correlations between the usefulness of conscientiousness for both doctors and sales clerks.
Big 5,
OCEAN,
Psychometrics,
personality traits in
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