Daily Archives: January 18, 2018

Sheldon Walker and the non-existent “slowdown”

Sheldon Walker has made yet another post at WUWT claiming there was a “slowdown” in global temperature recently, this time titled “Proof that the recent global warming slowdown is statistically significant (correcting for autocorrelation).”

The new post, rather than include “at the 99%% confidence level” at the end of its title as did the last one, has “correcting for autocorrelation.” There are two reasons for the title change. First, I’m not the only one who pointed out that his failure to account for autocorrelation invalidated his previous result; so did a brave few of the blog commenters. Kudos to Sheldon for not being so deep in denial that he rejected this fact.

Second, his new results (accounting for autocorrelation) didn’t seem to satisfy at the 99% confidence level, so he’s lowered the requirement to 90% confidence. The rationale he gives for doing so is silly; it truly amounts to nothing more than finding significance using higher confidence levels is hard. Nick Stokes points out, rather pointedly, “So you lower the level until you get a “significant” result?”

Continue reading