 In 2006, he published an article in the "Journal of Theoretical Biology", claiming that attractive people are 26% less likely to have male offspring.In a letter to the editors regarding Kanazawa's claim that attractive people are more likely to have daughters, Columbia statistician Andrew Gelman points out that a correct interpretation of the regression coefficients in Kanazawa's analysis is that attractive people are 8% more likely to have girls, an error that Kanazawa acknowledges.Gelman argues that Kanazawa's analysis does not convincingly show causality, because of possible endogeneity as well as problematic interpretations of statistical significance in multiple comparisons.