Here is an article from Slate on the fluctuating job market for academics in economics. I think the statistics would probably look the same for any field, though. It's called "What Ph.D. Students Really Have to Fear," and it's written by Joel Waldfogel. The gist is that if you are unlucky enough to graduate in a down cycle of the job market for your field, and you are not hired by a university of the same prestige level that you could have been hired by during an upswing in the market, you can expect to stay at a lower level throughout your career.
One interesting fact, though, is that the ones who were hired by more prestigious universities published more during their career. The author suggests that the better journals are more likely to publish articles from authors at prestigious universities. I'd be interested in the details of that statistic -- what I wonder is whether the more prestigious schools apply more pressure to publish in order to achieve tenure.
In researching this further by following the link in the article to the working paper by Paul Oyer, I can only access the abstract. However, he does state in that abstract that "better initial placement increases research productivity."
Two conclusions are possible (probably more, but this is all I can think of right now.) Either the universities that are more prestigious push more to have their professors publish, or there is some kind of negative effect that accrues to the people who are given the lower prestige job. They could be upset and bitter that the negative job cycle landed them in a less prestigious place, or it could be that these institutions demand more time teaching, being involved in committee and community work and the like.
It seems that a final piece of research would be to compare the two groups but control for their research productivity to see if the result is the same.