Science versus the stars: a double-blind test of the validity of the NEO Five-Factor Inventory and computer-generated astrological natal charts.

The authors asked 52 college students (38 women, 14 men, M age = 19.3 years, SD = 1.3 years) to identify their personality summaries by using a computer-generated astrological natal chart when presented with 1 true summary and 1 bogus one. Similarly, the authors asked participants to identify their true personality profile from real and bogus summaries that the authors derived from the NEO Five-Factor Inventory (NEO-FFI; P. T. Costa Jr. & R. R. McCrae, 1985). Participants identified their real NEO-FFI profiles at a greater-than-chance level but were unable to identify their real astrological summaries. The authors observed a P. T. Barnum effect in the accuracy ratings of both psychological and astrological measures but did not find differences between the odd-numbered (i.e., favorable) signs and the even-numbered (i.e., unfavorable) signs.