Yes, there are a few highly selective schools that don't have a Phi Beta Kappa chapter -- the service academies, Caltech, and Bryn Mawr among them. But many of those schools don't host GLO chapters on campus anyway, so their non-participation in PBK isn't relevant to the thread. (Many schools known for their excellent engineering or pre-professional programs do have chapters, such as MIT, Auburn, Texas A&M, etc.).
I don't believe all colleges and universities are equal in academic quality, and the marketplace doesn't believe that either. PBK is one of the better metrics to use if you want to put together a list of the 300 or so best undergraduate liberal arts programs in the country. Obviously a group that large is going to include more than just the Ivy League level institutions, but it's still an academically select group within the 2200+ four-year institutions in this country. So I was interested to see oldu's results, and if someone puts up an NPHC or MCGLO thread on the topic, I'll be interested in that, too.
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