I very much want the thesis of this article to hold true, but I have to wonder if the causal relationship in the article is reversed in reality. A quick skim d

I very much want the thesis of this article to hold true, but I have to wonder if the causal relationship in the article is reversed in reality. A quick skim didn't reveal anything, but is there any evidence against higher earners being afforded more time to sleep because of a high-paying job?