A 2013 paper by Adel, Hossain, and Johnson presented fi ndings that seem to support a tenet of astrology: the relationship between birth sign and celebrity. However, their fi nding was simply an artifact of assigning an arbitrary starting point to the zodiac signs and, consequently, the data do not support the validity of astrology.A 2013 paper by Adel, Hossain, and Johnson presented fi ndings that seem to support a tenet of astrology: the relationship between birth sign and celebrity. Verifi cation of this result would be surprising, fi rst, because previous research has not supported sun sign astrology (e.g., Jackson & Fiebert, 1980 ); and second, because the sun signs of popular astrology no longer coincide with the actual position of the sun against the Zodiac ( Culever & Ianna, 1988 ). Even some astrologers dismiss or downplay sun sign astrology (e.g., Kochunas, 2008 ).Adel, et al . ( 2013) looked at three samples of celebrity birth dates. The sample sizes were 100, 200, and 300, respectively. In each case, a signifi cant correlation between birth sun sign and number of celebrity births was reported. The reported Pearson's correlation coeffi cients were large for the three samples ( r = .47, r = .48, and r = .59, respectively) with the sun sign Aquarius showing the largest number of celebrity births for all three samples. However, the study was methodologically fl awed. In this paper I will explain the fundamental error made by the authors and re-analyze the data.In their analysis, Adel, et al . (2013 ) regressed the number of celebrities' births against the sun signs arranged in order from Aries to Pisces. Aries is given the value of 1, Taurus 2, and so on. The authors freely admit that this ordering is arbitrary, but claim "even if Aries is not marked by '1' by another data analyzer, neither the result nor the academic value changes as long as the consistency is maintained in all cases of assigning the numbers to the zodiacs" (p. 172). The central purpose of this paper is to demonstrate that this claim is false.
MethodIn this re-analysis I have used only the data from the largest sample of 300 celebrities. I have calculated the correlations between number of celebrity births and sun sign. However, I have run the analysis 12 times. In each case, I have used a diff erent sun sign as the starting point and assigned it the value of 1, and then from that point, counted off the remaining signs in order. All calculations were made in R.
ResultsThe results are shown in Table 1 . Some correlations are small and statistically nonsignifi cant ( r = .02, p = .96), while others are large and statistically signifi cant ( r = .59, p = .04); indeed, some correlations are large and negative ( r = -.45, p = .14). The results reported by Adel, et al . (2013 ) are an artifact of their ordering of the zodiac signs, a choice that they concede is arbitrary.
DiscussionSince there is no real zero point in the zodiac, the choice of Aries was arbitrary. While there has been a long tradition of listing Aries as the fi rst sign, this ...