Many Americans find astrology quite convincing. In fact, approximately 25% of Americans believe in Astrology, 55% of 18 to 24 year olds think astrology is at least “sort of scientific”, and a Huffington Post article on the Zodiac signs of world leaders, just released, has already accrued thousands of Facebook likes. My colleague Daniel Preotiuc-Pietro recently examined stereotypical words that accompany these beliefs by analyzing the content of tweets containing astrological sign hashtags. For example, my star sign, #leo, was most distinguished by words like “loyal”, “dynamic”, “stubborn”, “generous”, and “affectionate”. However, do leos actually differ in this way? Do people differ by their star sign at all?
I started investigating this question back in 2012 while working on what eventually became our first PLOS ONE paper: Personality, Gender, and Age in the Language of Social Media. My collaborators and I were thinking of applications for differential language analysis (DLA), our method which finds language features (e.g. words or phrases) that distinguish psychological and other human attributes. The suggestion was made that DLA could be used for psychological construct validation (i.e. does the language emerging from DLA fit the theory of the construct? How many language features, total, emerge as significantly correlated? For example, do leos use words indicating they are more stubborn or generous? How many words correlate with being a leo?).
Astrological (Zodiac) signs are a great way to prototype DLA for construct validation. Such signs seem to correspond with enduring traits that distinguish people. To believers, such signs are akin to a non-evidence-based Big 5 Personality Model, the most widely used model in Psychology. The Universal Psychic Guild represents this position:
The signs of the Zodiac can give us great insights into our day to day living as well as the many talents and special qualities we posses.
Daniel showed that differences clearly exist in descriptions of star signs. Here, we investigate whether differences clearly exist between people according to their star signs.