The Myth of Yield Protection Forum

[09042014]

I think that the majority of "YP!" claims are ego massaging, but I have read somewhere (and spoken to application counselors) who claim that it is real. Also, there are cases, like r6_philly, who was waitlisted at UCLA with a 3.9 CS degree and 170+ LSAT, plus a masters from an Ivy, while being getting $ at UVa. I am impressed by the statistical analysis that you did on LSN data (as any sabermetrician would be), but I think that the outliers in your model are proof of *some* YP, rather than the analysis proving that it does not exist.

To be clear, I'm tempted to scream YP about my WL's at Duke and especially UCLA, based on other people who I know have gotten in/$$, but my numbers really aren't so much better than their medians (they actually are below some of them) that I would be an auto admit.

Neither Duke nor UCLA YP. Sometime schools just don't like you.

My current cycle definitely shows a lot of schools just not liking me. My application was very specific and I don't think it's a coincidence that the same schools I want to attend also want me to attend while schools that were not high on my list waitlisted or rejected me.

There are schools that YP. Just not Duke and UCLA.

[birdlaw117]

I'm not convinced they don't practice any YP, but as a general rule I agree with you. I was just saying that sometimes a bad fit can look like YP (although with my numbers I'm not sure you would draw many YP conclusions).

[amers73]

Sometime schools just don't like you.

This.

[awilson11]

I think that the majority of "YP!" claims are ego massaging, but I have read somewhere (and spoken to application counselors) who claim that it is real. Also, there are cases, like r6_philly, who was waitlisted at UCLA with a 3.9 CS degree and 170+ LSAT, plus a masters from an Ivy, while being getting $ at UVa. I am impressed by the statistical analysis that you did on LSN data (as any sabermetrician would be), but I think that the outliers in your model are proof of *some* YP, rather than the analysis proving that it does not exist.

To be clear, I'm tempted to scream YP about my WL's at Duke and especially UCLA, based on other people who I know have gotten in/$$, but my numbers really aren't so much better than their medians (they actually are below some of them) that I would be an auto admit.

Neither Duke nor UCLA YP. Sometime schools just don't like you.

My current cycle definitely shows a lot of schools just not liking me. My application was very specific and I don't think it's a coincidence that the same schools I want to attend also want me to attend while schools that were not high on my list waitlisted or rejected me.

There are schools that YP. Just not Duke and UCLA.

If you had read my post correctly, you would see that I did not claim that I was YP'd at either school, just that I was tempted to claim it. To massage my ego. And also, you know this how? Explain r6_philly

[FiveSermon]

If you had read my post correctly, you would see that I did not claim that I was YP'd at either school, just that I was tempted to claim it. To massage my ego. And also, you know this how? Explain r6_philly

He already posted his explanation.

Sometimes schools just don't like you.

Don't question the Fox.

[Sandrew]

LOL at OP changing the weight of his index until he got the results he desired.

You don't get to call yourself an empiricist when you change your formula til you get results you want.

Haha. Yeah, that's pretty much what happened. But if you'll allow me the opportunity, I'd like to convince you that I wasn't being disingenuous.

Your charge is that I was being intellectually dishonest by toying with the index weights at each school in order to gin-up the results I was after. I'll admit to a methodological mistake (I already have), but I devised my methodology earnestly. It was flawed, but I wasn't trying to obfuscate.

That I used the iteration routine in the first place is not prima facie evidence of my dishonesty, although I understand how it would make you suspicious. So why did I iterate, if not to be sneaky? Statistics! (Well, bad statistics) Here was my thinking (more formalized than it was in my head), with methodological errors called out and footnoted:

I started with the null hypothesis that YP does not exist and the alternative hypothesis that it does. I then asked whether my null hypothesis explains the data. I had to come up with a test that would show whether the null hypothesis was rejected. So I asked what the data would look like if the alternative hypothesis were true. To me, YP means that a given school waitlists candidates for being over-qualified. If this were true, I surmised, then a given school would be more likely to accept certain "appropriately-qualified candidates" while waitlisting the most qualified ones (where "most qualified" means that they have strong numbers). I reckoned a single index combining relative LSAT and GPA among candidates was a reasonable proxy for quality [1]. But introducing the index also introduced another degree of freedom: the weights of LSAT/GPA in that index. Not having priors to go on (an intuition that might come from months or years of participating on these fora), I made what I thought was a reasonable assumption of 50/50 weights. But when I compared American's admissions data to Columbia's, I realized that different schools must use different weights. So I needed a routine to estimate the weights. The iterative routine made sense to me in the context of my null hypothesis. In other words, I was trying to see if the admissions data could be explained without relying on YP.[2]

[1] As user mst and others have pointed out, an index (no matter the weights) is not a good proxy. Some schools prefer LSAT scores to be over a certain threshold, but the returns on higher LSATs are diminishing (and, in the case of YP'ing schools, negative!). These schools treat splitters with a degree of caution. The same could be true of GPA. It boils down to the fact that the relationship between acceptance rate and each of LSAT and GPA is both nonlinear and multi-dimensional.
[Ed note: Final sentence added for clarity.]
[2] I see now that I presented my findings unfairly. My original UVA graph only showed that it's possible UVA does not YP; it did not show evidence that UVA does not YP. Absence of evidence is not evidence of absence; or, in statistical jargon, I mixed up my null and alternative hypotheses. An amateurish mistake--but hey, I'm an amateur!

Run the data with the published forumas that were posted a couple pages ago and repost.

I already posted the chart using 60/40 weights for UVA. I think this shows that you and others are correct about the weights, so no need to rub my nose in it. Further, I think the matrix I posted the other day is more informative. But I'm feeling generous, so here's the specific graph you're after:

[thsmthcrmnl]

Serious props to the OP for prompting an interesting conversation and for general maturity.

[birdlaw117]

I think in light of the happenings at Michigan today, now would be an appropriate time to bump this thread (hopefully it can remain pleasant and on-topic).

[09042014]

I think in light of the happenings at Michigan today, now would be an appropriate time to bump this thread (hopefully it can remain pleasant and on-topic).

What happened at Michigan.

[NZA]

I think in light of the happenings at Michigan today, now would be an appropriate time to bump this thread (hopefully it can remain pleasant and on-topic).

What happened at Michigan.

Torrent of WL.

[swampthang]

I think in light of the happenings at Michigan today, now would be an appropriate time to bump this thread (hopefully it can remain pleasant and on-topic).

What happened at Michigan.

Torrent of WL.

Conservative enrollment-management = YP? Two semi-relevant thoughts come to mind: 1. we might all be using terms with the same definitions. 2. Sandrew's early point that selectivity counts for far less (I believe the exact factor is 8x or 9x) than LSAT/GPA suggests that schools would be disincentivized from practicing YP since the small gain in selectivity comes at the price of not being able to chase high-index applicants.

I doubt we'll resolve the issue definitively, but it's certainly interesting to watch people prove the opposing viewpoints.

[WarioLaw]

I find it interesting that, outside of HYS, I have been admitted to all T14 that I applied to except UVA (waitlist) and Penn (still pending). So there is some anecdotal evidence that confirms your conclusions.

[bellamy]

I find it interesting that, outside of HYS, I have been admitted to all T14 that I applied to except UVA (waitlist) and Penn (still pending). So there is some anecdotal evidence that confirms your conclusions.

Likewise I have also been admitted to all T14 schools I applied to ( outside HYS) including CCN,Penn ,UVa,Duke,and GULC but was (like a whole bunch of other people with good numbers) waitlisted at Michigan.

[yale2011]

.