Compara mètodes

	Variables Instrumentals en la Recerca Educativa	Diferència en Diferències (Diff-in-Diff)
Camp	Inferència causal	Econometria
Família	Regression model	Regression model
Any d'origen	1991 (canonical education application)	1994
Autor original	Angrist & Krueger (canonical 1991 education application); grounded in IV theory by Wright (1928)	Card & Krueger (canonical 1994 application); Angrist & Pischke (textbook treatment)
Tipus	Quasi-experimental causal identification	Causal inference / panel regression
Font seminal	Angrist, J. D., & Krueger, A. B. (1991). Does Compulsory School Attendance Affect Schooling and Earnings? Quarterly Journal of Economics, 106(4), 979-1014.	Angrist, J. D., & Pischke, J.-S. (2009). Mostly Harmless Econometrics: An Empiricist's Companion. Princeton University Press. ISBN: 978-0691120355
Àlies	IV in education, 2SLS in education, education IV, school IV estimation	diff-in-diff, DiD, Farkların Farkı (Diff-in-Diff)
Relacionats	5	5
Resum	Instrumental variables (IV) estimation is a quasi-experimental strategy for isolating the causal effect of schooling or educational interventions when assignment to treatment is confounded by unobserved factors. Pioneered in education economics by Angrist and Krueger's use of quarter-of-birth as an instrument for compulsory schooling, IV finds a source of exogenous variation in exposure to education and uses only that variation to estimate outcomes such as earnings, test scores, or attainment.	Difference-in-Differences is a causal-inference method that estimates the effect of an intervention by comparing how a treatment group and a control group change over time. Made famous by Card and Krueger's 1994 minimum-wage study and developed in Angrist and Pischke's Mostly Harmless Econometrics, it isolates the treatment effect as the difference between the two groups' before-after changes.