<p>hawkette:</p>
<p>I just want to say how wonderful your series of data posts have been. The work you put into it is much appreciated. I always feel like a heel when I point out the limitations and, trust me, that’s not my sentiment at all. Great job.</p>
<p>Caveat emptor: On this one, most of the top schools now have under 50% of their students reporting class ranks. It is usually the top privates and publics who refuse to rank. Therefore, the validity and usefulness of this data is questionable and you are starting to see significant year to year fluctuations – not because the students are actually changing, but just as statistical noise depending on whether a particular year’s cohort comes from reporting or non-reporting high schools.</p>
<p>I would not use this data to make highly granular comparisons.</p>