That's the title of a paper that Royce de Rohan Barondes has posted on SSRN. Here's the abstract:

This paper analyzes the relationship between the law schools attended by non-permanent judicial clerks and the frequencies of two adverse signals assigned by Shepard's to their judges' opinions: either a negative (warning) signal (roughly equivalent to reversal) or a signal indicating the opinion's validity has been questioned. Using a sample of 12,966 opinions written by 95 federal district court judges, the portion of a judge's non-permanent clerks from Yale Law School is found to be positively related to the likelihood the opinion will have a negative (warning) or questioned signal, which is statistically significant at the 1% level. There is a negative relationship between the average reputation of the law schools a judge's clerks attended (better reputations being numerically higher) and the likelihood of his or her opinion having a negative or questioned signal, although that relationship is statistically significant in only some contexts.

As a Yale Law alum, I wish I could say that the paper's findings don't ring true. Alas, I cannot.