Monday, 10 January 2011

Rough Stats: More on University Admissions

Playing around with UCAS admissions data, looking at success rate of applicants by ethnicity. Mostly inspired by David Lammy's investigations and articles that led to a previous entry on here about low success rate of black applicants to Oxbridge.

Oxford hit back over the accusations, giving a fairly good account of itself as it identified various reasons for why black applicants might be few in number in the first place, as well as why they may have comparatively lower success rates in their applications. I've poked through the UCAS data for the last 6 years and looked at the success rate of different ethnic groups, comparing each to the 'average' success rate for that year. Here's a quick and dirty graph:

Some real food for thought there. Black applicants seem to consistently underperform, having a 10% lower chance of succeeding in their university application than the 'average' student. Those identifying themselves as white, Asian and 'mixed' all seem to hover around the average (although with applicants being around three-quarters white this group has a big sway in determining the average to begin with). 'Others' don't do too well either, maintaining a fairly steady -5%.

What's most peculiar, though, is the 'unknowns', who suddenly shoot up to overachieving as much as black applicants underachieve from 2006 onwards. In fact, they pretty much perfectly mirror the black applicants for those 4 years, including the jump from 2008 to 2009. Coincidence? No idea.

One could easily point at these data as proof of prejudice in university admissions, but to do so would be missing some pretty glaring questions. In Oxford's rebuttal of Lammy's accusations they point out that their black applicants tended to apply for their more competitive courses, which went at least some way to explaining their poorer success rate. Is there any reason to think this pattern isn't repeated on a national scale? Another big question is the unknowns - what data are hiding there? Is it reasonable to assume that those who choose not to disclose their ethnicity are representative of the entire applying population? I'm going to go with "probably not" (and at some point get around to flicking through the literature for a better answer).


  1. Is there any way of finding out if there's correlation between the number of mixed/dual ethnicity people coming of age between 2004-9 and the 'unknown' figure? I imagine many 'dual heritage' people tend to go for the 'prefer not to say/no answer' box. I hold no statistically sound proof, of course, but might be worth a look at.

  2. Yeah, the question of how 'unknowns' are distributed compared with the general population is quite an important one here, although my initial searches of the literature don't throw up anything explicit. There are standard methods one can employ, but you need access to the full dataset to use them. Looking at distributions (not that they seem easily available...) might be profitable, though, in case any patterns show up there which are reflected in the data that are available.