Chris Sims - RIP

I was saddened to hear of Chris Sims’s passing yesterday. Although I’m not a macroeconometrician, his work has strongly influenced the way I think about econometrics. I covered his famous helicopter tour paper on this blog a while back. Some of my other favorites are unpublished notes or slides from his website , many of them with a philosophical bent. Thinking about instrumental variables is a paper I read in grad school that really clarified why things can go so badly wrong in IV estimation. I