<p>In addition to the research statement, schools do consider the school you attended when making an admission decision. This happens for a couple of non-research related reasons. First, professors at top universities know each other. If Dr. Smith recommends Kamel Akbar, that recommendation goes farther if the review committee’s response is “Oh, I know Dr. Smith. She’s a great researcher.” rather than “Who is Dr. Smith?” </p>
<p>Second, everyone (schools and employers) tend to use undergraduate schools as a filter. To get into a school like Stanford, for instance, you had to be a highly motivated and accomplished high school student. And highly motivated and accomplished high school students tend to be highly motivated and accomplished college students. So it’s a quick and easy way to screen applications. </p>
<p>It wouldn’t matter where you went to school if you have a 3.9 GPA and 800 Math GRE, but someone who is average (let’s say a 3.3 GPA and 750 Math GRE with no publications and two semesters of reasonable research) can benefit greatly from school prestige, especially if you’re applying “down” to graduate schools with lower prestige than your undergraduate school.</p>