What Use Are Economists?

CAMBRIDGE – When the stakes are high, it is no surprise that battling political opponents use whatever support they can garner from economists and other researchers. That is what happened when conservative American politicians and European Union officials latched on to the work of two Harvard professors – Carmen Reinhart and Kenneth Rogoff – to justify their support of fiscal austerity.

Reinhart and Rogoff published a paper that appeared to show that public-debt levels above 90% of GDP significantly impede economic growth. Three economists from the University of Massachusetts at Amherst then did what academics are routinely supposed to do – replicate their colleagues’ work and subject it to criticism.

Along with a relatively minor spreadsheet error, they identified some methodological choices in the original Reinhart/Rogoff work that threw the robustness of their results into question. Most important, even though debt levels and growth remained negatively correlated, the evidence for a 90% threshold was revealed to be quite weak. And, as many have argued, the correlation itself could be the result of low growth leading to high indebtedness, rather than the other way around.

Reinhart and Rogoff have strongly contested accusations by many commentators that they were willing, if not willful, participants in a game of political deception. They have defended their empirical methods and insist that they are not the deficit hawks that their critics portray them to be.