<p>ivyleaguer - </p>
<p>using caltech is a poor example. at 900 students in a class and a very self-selecting pool, you aren’t really going to find caltech really showing the full potential of what college admissions is about. it is about balancing different kinds of students, with different interests, and still coming out with a very strong class.</p>
<p>its for that reason that i have a different thought about selectivity. sat score and class rank are ok, but rather poor measures of selectivity by themselves. because columbia and penn have the ability to select from a huge range of candidates with many in the top 10% of their class and many with top SAT scores (most of whom are rejected). we can’t really gain a good understanding of what columbia or penn could do if, let’s suppose, they only cared about admitting the students with the best scores and testing. therefore we need to think of a measure of selectivity that takes into consideration that ivy league schools do not admit only kids with the highest grades, and yet produce classes with strong academic metrics. </p>
<p>in short - we need to simulate in some way the ‘drag’ that comes in admitting kids who are in the lower quartile of a class, and in a sense we want to see if that drag is severe or not to academic metrics. so by measuring the stronger the drag - so the greater we could predict lower scores - and contrast it with actual sat/rank data, we could gain some understanding of who actually must be the most selective if a school has a high drag and still a high mean for academic metrics.</p>
<p>ideally i think we would want to add two populations i don’t think we can easily find data for - athletes and legacies. they are the most obvious drags out there because they tend to have the lowest test scores/rank. though there is something hard about dealing with athletes because the academic index itself means that schools have ‘controlled’ for how much of a drag athletes can be on most academic measures (i should say i once heard that the ivies compile all the AIs for all teams and note that each year harvard has the highest ai, followed by yale, princeton, columbia, and penn is 6th or 7th).</p>
<p>i would argue that the best place to turn is socioeconomic and ethnic diversity. in part because the data is pretty clear out there, we know a lot of things about mean scores for students from underrepresented backgrounds, and we know percentage of students attending various schools based on some of these measures (US news posts some data, individual schools are posting more and more their individual representations of students from various different ethnic categories).</p>
<p>i think this is a pretty strong idea because a) you’re testing the strength of students from underrepresented backgrounds that are being admitted, b) you’re also testing the pull strength of other students to maintain a high mean in SAT and other metrics, c) underrepresented minorities, especially, are often the most sought after students (i’d say science is more so, but no data really lets me tease that out) because the pool of very qualified is small this means they often represent the highest chance for cross admits. </p>
<p>schools such as penn, princeton and dartmouth that have high legacy rates would do well there. schools such as columbia, princeton and dartmouth that have the smallest student bodies would do well in athlete data because athletes probably make up the largest percentage of the student body there.</p>
<p>but columbia unequivocally comes on top among the ivy schools in socioeonomic and ethnic data. at 16% students on pell grants, columbia is ahead of harvard at 14% and penn at 11%, and has led the ivy league every year for the past 4 years. at 32% underrepresented minorities, they have the highest percentage there, 57% of the class overall is minority, also leading the ivy league. (penn is at 19% urm and 44% minority overall, far lower than cu.)</p>
<p>i’d say if you tallied up (and i do hope someone will sometime) all the drag data, you’d probably come up with some measure that says columbia probably has the largest drag (or students coming from populations that often form the lower quartile). this is confirmed at least to me because columbia has the smallest 25-75 SAT gap, which means their weaker students are not that weak in comparison to their stronger students. i’d guess that the next two most diverse schools, harvard and yale, probably also would do well in such a measure. i think that princeton would not be as strong as others, but their raw academic data isn’t strong enough for columbia to overtake them yet in selectivity data (that excludes admit rates).</p>
<p>so ultimately i think the fact that columbia has an 8 point gap over penn in SAT mean is more significant than you lead on. it is doing so despite the fact that it has a more diverse class with a greater potential that it should have a lower mean avg. it is also why i don’t think caltech really works in your example, because of the lack of drag at caltech they are able to admit a pretty uniform class with very high test scores, which i don’t think means they are more selective, just more unitary.</p>