قارن الطرق

	اختبار جذر الوحدة للوحدات المجمعة (LLC) من تطوير ليفين-لين-تشو	اختبار جذر الوحدة للوحات فيشر
المجال	الاقتصاد القياسي	الاقتصاد القياسي
العائلة	Hypothesis test	Hypothesis test
سنة النشأة	2002	1999
صاحب الطريقة	Andrew Levin, Chien-Fu Lin & Chia-Shang Chu	G. S. Maddala & Shaowen Wu
النوع	Panel unit-root test (homogeneous alternative)	Nonparametric combination-of-p-values panel unit-root test
المصدر التأسيسي	Levin, A., Lin, C.-F., & Chu, C.-S. J. (2002). Unit root tests in panel data: asymptotic and finite-sample properties. Journal of Econometrics, 108(1), 1–24.	Maddala, G. S., & Wu, S. (1999). A comparative study of unit root tests with panel data and a new simple test. Oxford Bulletin of Economics and Statistics, 61(S1), 631–652.
الأسماء البديلة	LLC Test, Panel Unit-Root Test (Homogeneous), Levin-Lin Unit-Root Test, Panel Birim Kök Testi (LLC)	Maddala-Wu Test, Fisher-type Panel Unit-Root Test, MW Panel Unit-Root Test, Fisher Panel Birim Kök Testi
ذات صلة	3	3
الملخص	The Levin-Lin-Chu (LLC) test, introduced by Levin, Lin, and Chu (2002), is a first-generation panel unit-root test that pools cross-sectional information to test whether all units in a panel share a common autoregressive unit root. It is widely used in applied economics and finance when researchers work with balanced or near-balanced panels and require a powerful test against a homogeneous stationary alternative.	The Fisher-type (Maddala-Wu) panel unit-root test, introduced in 1999, combines individual-level ADF unit-root p-values using Fisher's chi-squared meta-analytic framework to produce a single panel-level test statistic. Unlike the Levin-Lin-Chu approach, it does not impose a common autoregressive parameter across cross-sections, making it a natural choice for heterogeneous panels in macroeconomics, finance, and regional economics.