Σύγκριση μεθόδων

	Backtesting Αξίας σε Κίνδυνο (VaR)	Μοντέλο GARCH (Πρόβλεψη Μεταβλητότητας)	Παλινδρόμηση Ελαχίστων Τετραγώνων (OLS)
Πεδίο	Χρηματοοικονομικά	Οικονομετρία	Οικονομετρία
Οικογένεια	Regression model	Regression model	Regression model
Έτος προέλευσης	1998	1986	2019
Δημιουργός	Kupiec (1995); Christoffersen (1998); Engle & Manganelli (DQ test)	Tim Bollerslev	Wooldridge (textbook treatment); classical least squares
Τύπος	Statistical hypothesis tests on VaR violation sequences	Conditional volatility model	Linear regression
Θεμελιώδης πηγή	Kupiec, P. H. (1995). Techniques for Verifying the Accuracy of Risk Measurement Models. The Journal of Derivatives, 3(2), 73-84.	Bollerslev, T. (1986). Generalized Autoregressive Conditional Heteroskedasticity. Journal of Econometrics, 31(3), 307–327.	Wooldridge, J. M. (2019). Introductory Econometrics: A Modern Approach (7th ed.). Cengage Learning. ISBN: 978-1337558860
Εναλλακτικές ονομασίες	VaR backtest, Kupiec test, Christoffersen test, Dynamic Quantile test	GARCH, GARCH(1,1), conditional volatility model, GARCH Modeli (Oynaklık Tahmini)	ordinary least squares, classical linear regression, linear regression, en küçük kareler regresyonu
Συναφείς	3	5	5
Σύνοψη	VaR backtesting is a family of statistical tests that validate a risk model by comparing its Value-at-Risk forecasts against realised losses. It builds on Kupiec's (1995) unconditional coverage test, Christoffersen's (1998) conditional coverage test, and the Engle-Manganelli Dynamic Quantile (DQ) test.	The Generalized Autoregressive Conditional Heteroskedasticity (GARCH) model, introduced by Tim Bollerslev in 1986, models the time-varying conditional variance of a financial time series. It captures volatility clustering and the ARCH effect, and is the standard tool for estimating risk and volatility in return series.	Ordinary Least Squares is the classical linear regression method that explains a continuous outcome as a linear combination of predictors. It estimates the coefficients by minimising the sum of squared residuals, and under the Gauss-Markov assumptions these estimates are the best linear unbiased estimator (BLUE).