Seminar at Nuffield College, Oxford University on measuring inequality of educational opportunity in comparative stratification research (with Anders Holm). Chair: Erzsébet Bukodi (co-organiser). Discussants: David Cox, John Goldthorpe, and Jouni Kuha. Background paper: Breen, R, Holm, A, Karlson, KB. "Correlations and Non-Linear Probability Models." Forthcoming in Sociological Methods and Research.