The paper - I have not, the article - yes.

I've looked through the paper diagonally now, and since it's a scanned PDF, I'll get back to it to read it patiently.

I still see that they chose one criterion which is maybe less relevant for things I look for, which are usually not very popular. There's probably a curve somewhere which is better for Bing, apparently, than for Google in that point.

Because it's my personal experience that I find things much faster with Ecosia than with Google.