[jrflo]

I'm also surprised it's so low, because I feel that doesn't align with my anecdotal experience. Perhaps part of the problem is they only did the analysis on "...for freshman admission between 1994 and 2011 for whom complete data were available on all covariates". Perhaps wealthy families are less likely to submit family income data, or the income data is somehow related to FAFSA, in which case wealthy families will be under represented. Also note, they used family income as a proxy for SES, which is understandable but also not completely correct. Many wealthy people have no-to-low income for tax purposes.