I imagine the signaling is partly due to the selective admissions processes at elite universities. MIT, Stanford, Harvard already vetted for you, so surely you must be intelligent, driven and cut above the rest.

But I wonder if there are recent studies on the demographics of who attends elite universities in general? I'd assume it is mostly kids from the upper middle class to upper class backgrounds.

These sort of places pat themselves on the back for saying they do target minorities and the less privileged, but they have such an insurmountable background to overcome they may never make it to such schools, despite being smart enough to attend.

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