Environmental Economics

The headline should really read "Earning Doctorate During Recession 'Boosts Productivity'" of those in top 30 programs" (The Ticker):

Take heart: New research shows that scholars who earn Ph.D.’s during a recession are more productive in the long run—at least in the field of economics.

Michael Boehm, a researcher at the London School of Economics’ Centre for Economic Performance and Bonn University, looked at data from the top 30 universities in the United States from 1955 to 1994.

He found that among students of economics, those who completed their Ph.D.’s during a recession went on to produce comparatively more research during their careers, “a fact attributed to the stiff competition for jobs and a need to prove themselves.”

These studies of academics that only focus on the top programs always strike me as a bit odd. Why is that sample chosen? Are the top 30 program graduates more interesting? Is the data easier to collect?

As the title suggests, people extrapolate the results of a study of the top ranked programs to all programs. In statistics you might say that only looking at the top PhD programs produces a biased sample of all programs. The only conclusions that you can generate is applicable to those in top 30 programs. 

So we're not sure how this affected PhDs from the non-top 30 PhD programs. My guess is that it decreased their research productivity since they were less likely to land jobs at places that required high quality and high quantity research.