Saturday, April 20, 2013

A Lesson on Climate From a Non Lesson on Economics

"If true, this is embarrassing and worse for R-R (Reinhart-Rogoff). But the really guilty parties here are all the people who seized on a disputed research result, knowing nothing about the research, because it said what they wanted to hear." - Paul Krugman.

In a way this sounds a bit familiar, but instead of climate its economics.

If your not familiar with Reinhart-Rogoff (nber.org/papers/w15639.pdf), I'll give a very short version.

R_Rcorrect (1)
Difference between R-R and Herndon, Ash and Pollin
Figure from Jared Bernstein

R-R wrote a paper on debt and gross domestic product ratios. One of the ratios was turned into a sound bite you may have even heard as a fact: If debt/GDP exceeds 90%, GDP will become negative (see above figure) or a derivative of that sound bite. Problem was the paper was met with a bit of controversy and debate amongst economists. This was in part because there were a number of circumstances that did not meet the results that R-R suggested. Another issue is that even though debt/GDP ratios might have a correlation, that correlation could well be that when an economy is in crisis government revenues decline and government costs increase - that is the debt is the result of a lower GDP.

Herndon, Ash and Pollin (umass.edu/fileadmin/pdf/) were unable to replicate the R-R results so R-R shared their data (very commendable) and HAP found three areas of errors. One was an Excel spread sheet coding error, but there were two other errors that skewered the results.

But a broader policy issue is that even though the paper had not been well received or had the results confirmed, policy makers and pundits of a particular bent seized upon the paper to justify economic policy. An economic policy of austerity.

The federal austerity policy will have an impact on Washington State and that impact may be larger here than elsewhere due to the large military bases and military contracts as well as the Hanford Department of Energy cutbacks.

While climate science has been politicized, it has nothing on economics. Political tribes hear what they want to hear and gladly push forward as brilliant any study or paper that supports what they want to hear regardless of how poorly it is received amongst experts in the field. Sounds sort familiar post WA Senate Climate Fuss.

1 comment:

Bert Rubash said...

"so R-R shared their data (very commendable)"

Commendable? I think it was improper not to have made it available from the start as supplemental material along with publication, or at least immediately available from the corresponding author. Publication of scholarly work can't be merely advertising of results or conclusions, but must include whatever is necessary to enable others to arrive at the same conclusions.

An important factor that keeps Don Easterbrook's work from being scholarly work is that he steadfastly ignores requests for the data he uses for his graphs and conclusions, and Doug Ericson is also ignoring such requests.

Bert Rubash