قارن الطرق

	اختبار جذر الوحدة Zivot-Andrews متغير المعلمات عبر الزمن	اختبار Zivot-Andrews للكسر الهيكلي
المجال	الاقتصاد القياسي	الاقتصاد القياسي
العائلة	Regression model	Regression model
سنة النشأة	1992 (base test); TVP adaptation in later applied work	1992
صاحب الطريقة	Zivot & Andrews (1992); TVP extension in subsequent applied econometrics literature	Eric Zivot and Donald W. K. Andrews
النوع	Unit root test with endogenous structural break under time-varying parameters	Unit root test with endogenous structural break
المصدر التأسيسي	Zivot, E., & Andrews, D. W. K. (1992). Further Evidence on the Great Crash, the Oil-Price Shock, and the Unit-Root Hypothesis. Journal of Business & Economic Statistics, 10(3), 251–270.	Zivot, E., & Andrews, D. W. K. (1992). Further evidence on the great crash, the oil-price shock, and the unit-root hypothesis. Journal of Business & Economic Statistics, 10(3), 251–270.
الأسماء البديلة	TVP Zivot-Andrews test, time-varying Zivot-Andrews unit root test, TVP-ZA test	ZA test, Zivot-Andrews unit root test, endogenous structural break unit root test, ZA structural break test
ذات صلة	6	6
الملخص	The time-varying parameter Zivot-Andrews test extends the classic Zivot-Andrews (1992) structural break unit root test by allowing the regression coefficients to evolve over time. Rather than assuming fixed parameters across the full sample, this approach lets the autoregressive dynamics and break timing adapt through a state-space or rolling framework, improving robustness when economic relationships shift gradually.	The Zivot-Andrews (ZA) test is a unit root test that endogenously identifies the most likely location of a single structural break in a time series. Unlike the standard ADF test, it does not require the researcher to pre-specify when the break occurred, making it robust to data-driven regime shifts such as policy changes, financial crises, or major economic events.