@jaror@social.edu.nl In particular, I promised myself No New Research. I tried to do that on my previous sabbatical, seven years ago, and got sidetracked by https://doi.org/10.1145/3236779. And on the sabbatical before that, another seven years earlier, and got sidetracked by https://doi.org/10.1145/2034773.2034777. I'm proud of both those papers, but they didn't get the book written!