The more equal women's opportunities compared to men's, and the more resources women have, the more their preferences differ from men's, suggests a new study based on survey data from nearly 80 countries. The finding reinforces one of two competing hypotheses on patterns of gender differences with respect to economic development and gender equality; namely, that the gender gap in fundamental preferences - those concerning time, risk and social interactions - becomes wider in populations where gender equality and economic development are greater. The results offer a key explanation for the differences in choices and outcomes between women and men concerning occupation, financial investments and educational decisions, among others, as well as their variability across countries and cultures worldwide. Although the origins of gender-associated differences in preference and their effect on the social and economic gap between the genders have long been of interest, what contributes to them is not well-understood. Of the two main competing hypotheses, one says that gender differences in preferences narrow in more developed, gender-egalitarian countries, while the other says they expand in such settings, where both women and men obtain sufficient access to resources to "independently develop and express their intrinsic preferences." In this study, Armin Falk and Johannes Hermle assessed the gender preference gap in relation to economic development and gender equality leveraging data from a Global Preference Survey of 80,000 individuals in 76 countries worldwide. Collected as part of a 2012 Gallup World Poll, the dataset contains measures of six fundamental preferences: the willingness to take risks, patience, altruism, positive and negative reciprocity, and trust. Falk and Hermle compared preference data at the country level, as well as how it related to variables such as GDP and levels of gender inequality. The authors' results show that differences in preferences between men and women were more distinct with increasing economic development and gender equality. The stronger differentiation in preferences observed in more developed and gender-equal counties could be supported by an increased empowerment for female self-expression and by women's increased capacity to resist social influence, according to the authors. The data on preferences by country are available in an Excel file on the press package page.