Maxwell's Demon, is a cute little bunny who sits at the door between two bags of wind. When the Demon sees a fast one coming from the right side she (the ladies are demons of course and the guys ogres, you never heard of Maxwell's ogre, did you?) opens the door and lets it through, but blocks the slow ones. This lead to a paradox which was only solved when it was realized that the Demon did not work for free energy.
Which brings us to today's post. Richard Tol has published a correction to 'The Economic Effects of Climate Change" which appeared in the Journal of Economic Perspectives (2009), with an interesting start
Gremlins intervened in the preparation of my paper "The Economic Effects of Climate Change" published in the Spring 2009 issue of this journal. In Table 1 of that paper, titled "Estimates of the Welfare Impact of Climate Change," minus signs were dropped from the two impact estimates, one by Plambeck and Hope (1996) and one by Hope (2006). In Figure 1 of that paper, titled "Fourteen Estimates of the Global Economic Impact of Climate Change," and in the various analyses that support that figure, the minus sign was dropped from only one of the two estimates.Get Energy Smart Now parses the correction
“minus signs were dropped … minus sign was dropped”.
Who dropped those minus signs and “overlooked estimates”. Evidently, those unnamed and nefarious “gremlins” who ”intervened” to undermine the quality of Professor Tol’s research and publications.
Using the passive voice makes one wonder whether editors, research assistants, technical glitches, or Professor Tol, himself, were the “gremlins” who “intervened”.without realizing that Tol's Demon is unidirectional
Richard was pushed to his correction by Bob Ward of the Grantham Insitute who looked at the original paper and commented on the possibility that these errors influenced the IPCC report and various EPA reports that referenced the FUND model and this paper. Richard is his usual gracious self in describing the situation. Get Energy Smart has some of the better details of the flame war that ensued with links, and Richard's acknowledgement is sweet
I am grateful to Bob Ward for finding a small error, to Mike Mastandrea for finding a bigger one, to Doug Arent for checking things again and again, to David Autor and Tim Taylor for their understanding, and to Ann Norman for superb editorial support. All remaining errors are, of course, mine and mine only.ATTP has a post on the meaning of the correction which references to Grant McDermott's take on this especially when he removes the single hugely positive value, from guess whom, Tol's One Way Demon
This, will be chewed on by many, however Eli wants to point to a comment by Grant in the discussion
The most famous IAM, William Nordhaus’s DICE model, using a quadratic damage function that is calibrated on Tol (2009)… But offset by an (arbitrary) 25% adjustment factor to account for the many accounted factors such as biodiversity loss, extreme events, etc (see page 10, 11 here). The function in question is: D(T) = 0.00267*T + 0.00267*T^2, where T is change in global surface temperature relative to the pre-industrial period.Eli, being a RTFR type of bunny went and RTFR, which reads
The 2013 model (DICE-ER) instead uses a highly simplified damage function that relies on current estimates of the damage function. More precisely, DICE-2013 uses estimates of monetized damages from the Tol (2009) survey as the starting point.Extra carrots if to anybunny who figures out what the Tol (2009) survey is.