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Title: Local Projections and VARs Estimate the Same Impulse Responses
We prove that local projections (LPs) and Vector Autoregressions (VARs) estimate the same impulse responses. This nonparametric result only requires unrestricted lag structures. We discuss several implications: (i) LP and VAR estimators are not conceptually separate procedures; instead, they are simply two dimension reduction techniques with common estimand but different finite‐sample properties. (ii) VAR‐based structural identification—including short‐run, long‐run, or sign restrictions—can equivalently be performed using LPs, and vice versa. (iii) Structural estimation with an instrument (proxy) can be carried out by ordering the instrument first in a recursive VAR, even under noninvertibility. (iv) Linear VARs are as robust to nonlinearities as linear LPs.  more » « less
Award ID(s):
1851665
PAR ID:
10281002
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Econometrica
Volume:
89
Issue:
2
ISSN:
0012-9682
Page Range / eLocation ID:
955 to 980
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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