השוואת שיטות

	מבחן שורש יחידה ADF עם שבר מבני	מבחן שורש היחידה של פיליפס-פרון
תחום	אקונומטריקה	אקונומטריקה
משפחה	Regression model	Regression model
שנת המקור	1989-1992	1988
הוגה השיטה	Perron (1989); Zivot and Andrews (1992)	Peter C. B. Phillips and Pierre Perron
סוג	Unit root test with structural break	Hypothesis test (unit root)
מקור מכונן	Perron, P. (1989). The great crash, the oil price shock, and the unit root hypothesis. Econometrica, 57(6), 1361-1401.	Phillips, P. C. B., & Perron, P. (1988). Testing for a unit root in time series regression. Biometrika, 75(2), 335–346.
כינויים	ADF with structural break, Perron unit root test, break-augmented ADF, unit root test with structural change	PP test, PP unit root test, Phillips-Perron test, nonparametric unit root test
קשורות	6	5
תקציר	The structural break ADF unit root test extends the standard Augmented Dickey-Fuller test to allow for one or more discrete shifts in the level or trend of a time series. Because ignoring a structural break inflates the apparent persistence of a series, this test prevents false acceptance of the unit root null when the series is actually stationary around a shifting mean or trend.	The Phillips-Perron (PP) test is a nonparametric unit root test for time series that corrects for serial correlation and heteroscedasticity in the error term without adding lagged differences. Introduced by Phillips and Perron (1988), it applies a kernel-based long-run variance estimator to adjust the Dickey-Fuller statistic, making it robust to a wide class of weakly dependent error processes.