Can Astrology Predict E and N? 3. Discussion and further research

Author: Dean, Dr. Geoffrey
Abstract: The validity of E (extraversion) and N (emotionality) for testing astrology is reviewed in detail (60 references) and is found to be adequate in every respect. The conclusions of Parts 1 and 2 are confirmed after the most critical scrutiny, comparison with other studies, and investigation of issues raised by readers. Much previously unpublished work is presented including a survey of the perceived discernibility of human characteristics in birth charts, Pierce’s factor analysis of astrological symbolism, a meta-analysis of 14 studies of astrologer agreement, the distribution of variance between astrologers and charts, a meta-analysis of 31 Vernon Clark results, a new Vernon Clark test of everyday topics, a comparison of the reliability and validity of astrology with that of other diagnostic tests, and an extension of Startup’s power analysis of astrological effects. The picture that emerges consistently from all of this work is that astrology as applied by astrologers using the whole chart has negligible reliability and validity. Aggregating astrologers improved the reliability as expected but had no effect on the hit rate, which remained close to chance level. The upper bound to the variance accounted for by astrological effects is orders of magnitude smaller than that required to meet the claims of astrologers.
Keywords: EPI, power analysis, trait theories, Vernon Clark tests, extraversion(E), emotionality(N)
Notes:Errata regarding Parts 1 and 2 are detailed on p52 of this article
Publication: Correlation: Astrological Association Journal of Research Into Astrology
Issue: Volume 6 Issue 2
Dated: 1986
Pages: Pages 7 – 51