Shub Niggurath @ Watts Up With That:
In 2012, Stephan Lewandowsky and co-authors submitted a paper to the journalPsychological Science, generating widespread publicity. Here, I address a simple issue/question that has hovered around the paper from the time it made its appearance. The issue is at the heart of Lewandowsky’s first ‘Moon Hoax’ paper and the now in limbo second paper in Frontiers in Psychology.
The ‘Moon Hoax’ paper (a.k.a LOG12, LOG13 etc) draws a number of conclusions about climate skeptics (called ‘deniers’). A major portion of the data and analysis is devoted to ‘rejection of climate science’. The paper’s title advertises its findings about ‘deniers’.
So the question is: how did Lewandowsky and co-authors actually study climate skeptics?
The answer may surprise you.
The paper draft (pdf) stated simply that authors ‘approached’ 5 skeptic blogs to post a survey, but ‘none did’. This lead to a hunt to find who exactly these bloggers were (Lewandowsky wouldn’t tell). Lewandowsky spread significant amounts of distraction and smoke on the matter, raising hue and cry that he did email skeptical bloggers:
First out of the gate was the accusation that I might not have contacted the 5 “skeptic” bloggers, none of whom posted links to my survey. Astute readers might wonder why I would mention this in the Method section, if I hadn’t contacted anyone.
What matters however, is not whether or not Lewandowsky contacted skeptics but what came of such contact. The whole point of contacting the bloggers was to get surveys posted on their websites to ensure skeptic participation. This never took place. Through the noise, the question of non-sampling of skeptics remained unresolved‡.
As a way of providing answer, the paper itself appeared in final form about a month back. When examined, the authors appear to have settled on a remarkable method of addressing the defect. In the supplementary information, Lewandowsky et al (LOG13) make a startling claim. They state the blogs that did carry their survey have a broad readership ‘as evidenced by the comment streams’:
All of the blogs that carried the link to the survey broadly endorsed the scientific consensus on climate change. As evidenced by the comment streams, however, their readership was broad and encompassed a wide range of view on climate change.
The authors claim to have analysed reader comments at one venue to determine this. They state:
To illustrate, a content analysis of 1067 comments from unique visitors tohttp://www.skepticalscience.com, conducted by the proprietor of the blog, revealed that around 20% (N = 222) held clearly “skeptical” views, with the remainder (N = 845) endorsing the scientific consensus.
Extrapolating, the authors infer further that close to eighty-thousand skeptics saw Lewandowsky’s survey on Skepticalscience alone (see below). Owing to such broad readership, enough skeptics are said to have been exposed to the survey.
Readers of climate blogs will at once see several things that are off. However, these are the assertions forming the basis on which Lewandowsky et al 2013 rests.
To start, the authors’ premises are accepted. It is deemed that comment streams can be analysed to determine whether a blog has a broad readership, or a more polarized one.
Comments on six blogs where Lewandowsky et al’s survey was posted were analysed. Commenter names and comment counts were obtained from web pages using R scripts. Following the authors’ method, this was carried out for the entire month the survey was posted. For each blog, duplicates were removed.
Commenters were classified as (a) skeptic, (b) ‘warmist’ (c) ‘non-skeptic’ (d) lukewarmer, (e) neutral, or (e) indeterminate. Regulars whose orientations are familiar (e.g., dana1981 – ‘warmist’) were tagged first. Those with insufficient information to classify, and infrequent posters with singleton comments were tagged ‘indeterminate’†.
The results are presented below. A total of 614 commenters contributed 4976 comments to six blogs in the month the survey was posted (range: 2 – 2387 comments/blog). An estimated 111 commenters posted across blogs, with 504 unique commenter aliases from all blogs.
The results show a skewed commenter profile. As a whole, there are 59 skeptical commenters, amounting to about 9.5% of total. Individually, skeptics range from 5-11% of commenters between blogs, with one venue (Hot Topic) showing 19% skeptics. Closer examination shows this to be made up by just 10 commenters. Non-skeptics are close to 80%, i.e., 480 of 614. Neutral posters are 9%, and indeterminate 3%. Of the 59, more than half are from comments posted at one blog (Deltoid).