1/Chris Sims is easily one of the most influential macroeconomists (& perhaps most influential empirical macroeconomist) of the last 50 years; he fundamentally changed thinking about monetary policy, metrics,& causality (VARs, time series models). Thread on his greatest hits🧵👇
@ProfPHansen As far as I know, White did it before but did not have PSD. It seems this is why NW emphasized the importance of PSD in the title and paper.
@ProfPHansen Very interesting! I do not have access to Gallant's. Did he also have a proof for positive semi-definiteness? Or did he show/mention this property? Newey-West has a proof which is different from the usual argument based on rewriting the LRV estimator in terms of the periodogram.
@ProfPHansen Yet, it is true that the Newey-West estimator was already considered in early work in stats. It is just that the theoretical result in Newey-West is more general.
@ProfPHansen Given that covariance-stationarity never holds in practice (e.g., breaks) and OLS does not require covariance-stationarity to be valid, the applicability of Newey-West's result is much broader than that of previous results in stats.
Honored to receive the Carlo Giannini prize at #ICEEE2023. I have seen several great papers presented by other junior people who deserve the prize as much as me. So ultimately receiving it means a lot to me. @LorenzoTrapani1@lucafanelli5@CavaliereGiu@SIdE_IEA
As is traditional, at #ICEEE2023 we awarded the Carlo Giannini prize. I was privileged to be chairing the awarding committee, and may I offer my congratulations to the winner, the great @AlessCasini - well done you wonderboy!!!
@J_ArellanoBover@Yale@YaleSOM@YaleEconomics@BarbaraBiasi Congrats Jaime! You are a very kind guy and very professional. There should be more people like in the profession. Great to had you as a colleague. I wish you guys all the best for the next step!
Causality in Econometrics: Choice vs Chance
Guido Imbens' @NobelPrize Lecture on causal inference, with an overview of much of the history of econometrics. @guido_imbens
https://t.co/kiVHlVqPP6