Comparer des méthodes

	Location Quotient	Shift-Share IV
Domaine	Économie	Inférence causale
Famille	Process / pipeline	Regression model
Année d'origine	1960	2020
Auteur d'origine	Developed in regional science; codified by Walter Isard	Bartik (1991); identification framework by Goldsmith-Pinkham, Sorkin & Swift (2020) and Borusyak, Hull & Jaravel (2022)
Type	Descriptive index of relative regional concentration	Instrumental-variable design
Source fondatrice	Isard, W. (1960). Methods of Regional Analysis: An Introduction to Regional Science. Cambridge, MA: MIT Press. ISBN: 9780262090032	Goldsmith-Pinkham, P., Sorkin, I. & Swift, H. (2020). Bartik Instruments: What, When, Why, and How. American Economic Review, 110(8), 2586–2624.
Alias	LQ, Coefficient of Localization, Regional Specialization Ratio	Bartik instrument, shift-share instrument, Shift-Share Araç Değişkeni (Bartik Instrument)
Apparentées	3	5
Résumé	The location quotient (LQ) is a simple descriptive index that measures how concentrated an industry is in a region relative to a larger reference area, usually the nation. It is the ratio of the industry's share of local employment (or output) to its share of national employment. An LQ above one means the region is more specialized in that industry than the nation as a whole; an LQ below one means it is under-represented.	The shift-share instrumental variable, widely known as the Bartik instrument, is a causal-inference strategy that builds an instrument by interacting national or sector-level shocks (the shifts) with local composition weights (the shares). Its modern identification framework was set out by Goldsmith-Pinkham, Sorkin and Swift (2020) and Borusyak, Hull and Jaravel (2022).