In fact we want to know that how division of society can be measured. How social differences among different people living in a society can be measured by taking into account different aspects such as education, health, ethnicity, language and gender etc.
I think it could be measured by classifying the society into classes depending on some variables as gender, region, religion, education, family huge,... etc , and measure every class separately, it will give a good results.
You can find some related stuff in the book "The Difference: How the Power of Diversity Creates Better Groups, Firms, Schools, and Societies" by Page, Scott. published by Princeton University Press, 2007
This book is more about the benefits of diversity and builds very compelling argument in its favor but it does discuss the dynamics of diversity as well as some models that help study and understand the social differences.