Assessment Methods for Measuring Value at Risk Based on the Hit Function

The aim of this paper is to provide tools to aid the management process of Financial Risk. Backtesting is the necessary procedure to choose and to evaluate the stability of a value at risk (VaR) models. This paper presents some typical, statistical methods based on the hit function. Advantages and d...

Повний опис

Збережено в:
Бібліографічні деталі
Опубліковано в: :Электронное моделирование
Дата:2009
Автор: Skrodzka, W.
Формат: Стаття
Мова:Англійська
Опубліковано: Інститут проблем моделювання в енергетиці ім. Г.Є. Пухова НАН України 2009
Онлайн доступ:https://nasplib.isofts.kiev.ua/handle/123456789/101528
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Цитувати:Assessment Methods for Measuring Value at Risk Based on the Hit Function / W. Skrodzka // Электронное моделирование. — 2009. — Т. 31, № 6. — С. 55-64. — Бібліогр.: 9 назв. — англ.

Репозитарії

Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1860199069229514752
author Skrodzka, W.
author_facet Skrodzka, W.
citation_txt Assessment Methods for Measuring Value at Risk Based on the Hit Function / W. Skrodzka // Электронное моделирование. — 2009. — Т. 31, № 6. — С. 55-64. — Бібліогр.: 9 назв. — англ.
collection DSpace DC
container_title Электронное моделирование
description The aim of this paper is to provide tools to aid the management process of Financial Risk. Backtesting is the necessary procedure to choose and to evaluate the stability of a value at risk (VaR) models. This paper presents some typical, statistical methods based on the hit function. Advantages and disadvantages of those methods are discussed in this paper. In the proposed approach to risk measurement, special attention is paid to the use of the Monte Carlo simulation along with the copula relation function in VaR methodology. Предложены средства управления финансовыми рисками. Обратное тестирование — необходимая процедура при выборе и оценивании пригодности моделей оценки риска. Представлены некоторые типичные статистические методы на основе функции совпадения. Описаны преимущества и недостатки этих методов. В предложенном подходе к управлению рисками особое внимание уделено моделированию методом Монте-Карло, а также функции связки в методологии оценки величины рисков. Запропоновано способи управління фінансовими ризиками. Зворотнє тестування — необхідна процедура для вибору та оцінки придатності моделей оцінювання ризиків. Наведено деякі типові статистичні методи базовані на функції збігу. Показано переваги та недоліки цих методів. Окрему увагу приділено моделюванню методом Монте-Карло, а також функції зв’язки у методології оцінки величини ризиків.
first_indexed 2025-12-07T18:09:39Z
format Article
fulltext W. Skrodzka, PhD Czestochowa University of Technology (Al. Armii Krajowej 19B,42-200 Czestochowa, Poland) Assessment Methods for Measuring Value at Risk Based on the Hit Function The aim of this paper is to provide tools to aid the management process of Financial Risk. Back- testing is the necessary procedure to choose and to evaluate the stability of a value at risk (VaR) models. This paper presents some typical, statistical methods based on the hit function. Advan- tages and disadvantages of those methods are discussed in this paper. In the proposed approach to risk measurement, special attention is paid to the use of the Monte Carlo simulation along with the copula relation function in VaR methodology. Ïðåäëîæåíû ñðåäñòâà óïðàâëåíèÿ ôèíàíñîâûìè ðèñêàìè. Îáðàòíîå òåñòèðîâàíèå — íåîáõîäèìàÿ ïðîöåäóðà ïðè âûáîðå è îöåíèâàíèè ïðèãîäíîñòè ìîäåëåé îöåíêè ðèñêà. Ïðåäñòàâëåíû íåêîòîðûå òèïè÷íûå ñòàòèñòè÷åñêèå ìåòîäû íà îñíîâå ôóíêöèè ñîâïà- äåíèÿ. Îïèñàíû ïðåèìóùåñòâà è íåäîñòàòêè ýòèõ ìåòîäîâ.  ïðåäëîæåííîì ïîäõîäå ê óïðàâëåíèþ ðèñêàìè îñîáîå âíèìàíèå óäåëåíî ìîäåëèðîâàíèþ ìåòîäîì Ìîíòå-Êàðëî, à òàêæå ôóíêöèè ñâÿçêè â ìåòîäîëîãèè îöåíêè âåëè÷èíû ðèñêîâ. K e y w o r d s: back- testing, value at risk, hit function, copula function. Introduction. In times of economic crisis, risk management gains on its impor- tance. The outcome of this crisis can be observed in every branch of business ac- tivity. No matter which economic sector we are dealing with, risk identification and management, including its assessment, should be a stable element of com- pany management in the strategic perspective. Last years have confirmed the ne- cessity of applying an approach to risk management which relies on the analysis of possible negative divergences from prices or from rates of return. The meth- odology based on such an approach is commonly known as downside risk mea- sures. The most popular of the downside risk measures described in literature is referred to as value at risk (VaR). Computing the VaR boils down to forecasting the p-quantile of a certain cumulative distribution function [1]. If the function were known, computing the exact VaR with the use of mathematical analysis or numerical methods would be an easy task. Owing to the peculiar properties of financial time series, however, it is not easy to estimate the extreme quantiles of the cumulative distribution function in ISSN 0204–3572. Ýëåêòðîí. ìîäåëèðîâàíèå. 2009. Ò. 31. ¹ 6 55 question. One also has to make an estimate of the VaR itself, using the analyses of rates of return from the risk factors and at the same time making appropriate assumptions concerning their distribution. This, in turn, means building up a whole econometric model. During the initial phase of the measurement process, one does not have the knowledge that follows from the methodology of VaR measurement — then again, the model that has been applied is considered ac- ceptable. What is necessary then is a procedure called back testing, which allows for the verification of the risk level that has been estimated. It also answers the question whether the approach that has been applied is optimal as regards the cri- terion that has been assumed. That kind of action becomes particularly important in the situation of increased instability of financial markets. The paper presents selected methods of assessing the VaR results that make use of hit function analysis. Back testing was applied to VaR assessment com- puted with the use of classical methods: the method of historical simulation, the method of variance-covariance, and the Monte Carlo method of simulation using copula relationships. The risk factors assumed are WIBOR 6M and WIBOR T/N interest rates (Warsaw Interbank Offered Rate), listed in the inter-bank market. This paper uses �-stable distributions and different kinds of functions of copula relationships for modeling the real distributions of rates of return for WIBOR in- terest rates. The purpose of this paper is presenting the tests for assessing the quality of VaR measurements, assessing the independence of VaR failures and answering the question which of the measurement methods concerned allows for the more successful risk assessment. Classical tests of VaR model assessment. Value at risk has been defined in the publications by the authors such as [1—3]. Value at risk is a maximal amount of money that can be lost as a result of portfolio investments having a fixed time span and an assumed level of relevance. It can be expressed in the following way: P W W{ }� � � 0 VaR � , where W0 — the recent value of e.g. instrument, portfolio or institution; W — the value of e. g. instrument, portfolio or institution at the end of the period; � — tolerance level. In this paper, VaR is considered as the appropriate quantile of the distribution of rates of return. VaR r t r tq F q , , ( ) ( )� � �1 . The definitions quoted above give the possibility of choosing several different approaches towards the measurement of the VaR. Among the classical methods we can distinguish: the historical method, Monte Carlo simulation, variance- covariance method and the methods based upon the theory of extreme values [3]. The existing methods of estimating the VaR can be divided in the following W. Skrodzka 56 ISSN 0204–3572. Electronic Modeling. 2009. V. 31. ¹ 6 manner : parametrical methods, non-parametrical methods, simulations, analyti- cal methods. Widely-understood methodology can lead to different estimates of VaR. A necessary procedure that allows for the verification of the correctness of VaR models is the process of back-testing. The process makes it possible for one to test the correctness of generated results and pin point every potential mistake, which in turn allows for the verification of the models adopted. It contributes to the improvement of the quality of risk measurement. Historical analysis also al- lows one to assess the effectiveness of the decisions that have been made with re- spect to past periods of business activity, and to introduce changes in already-ex- isting models. That type of analysis is very useful in improving the deci- sion-making process with respect to market risk management. Absolute agree- ment of actual and forecast positions is never possible, although the differences between the loss forecast with certain probability and actual results should be confined within the limits of error. The degree of error is the measurement of ef- fectiveness of the methods employed and of the potential verifications of the as- sumption that have been made. Value at Risk models can be analyzed via the comparison of calculation re- sults with the actual losses that are discussed in this paper, or via the assessment of the quality of the econometric models forming the base of the VaR model. In order to assess the effectiveness of VaR estimates, several hit functions are used — most commonly [4—6]. Hit functions have been defined in the fol- lowing manner: I r F q r F q t p t rp t p t rp t � � � � � � � 1 0 1 1 , ( ), , ( ). , , , , It assumes the value 1 if at the moment t the rate of return from the portfolio is smaller or equals the appropriate quantile — that is to say, when the VaR has been exceeded, and 0 if the VaR has not been exceeded. The test that is employed most frequently is called Proportion of Failures Test — POF, proposed in 1995 by P. Kupiec. For the purposes of the test one has to assume that for a given size of the theoretical sample, the number of failures has a binominal distribution. Appropriate test statistics would be Kupca’s test — Kupca [5]: LR q q q q uc T T T T � � � � � � � � � � 2 1 1 0 1 0 1 ln ( ) ( �) � , where �q T T T � � 1 0 1 , Assessment Methods for Measuring Value at Risk Based on the Hit Function ISSN 0204–3572. Ýëåêòðîí. ìîäåëèðîâàíèå. 2009. Ò. 31. ¹ 6 57 in which Ti — the number of periods in which It = i; q — assumed level of VaR tolerance. The LRuc statistics has the distribution of � 2 with one degree of freedom. The critical value of Kupiec’s test for the most commonly considered level of relevance 0.05 equals CV = 3.8415. The zero hypothesis concerning the VaR model is rejected if LRuc > CV. Using the idea of Markov’s chains, Christoffersen proposed test statistics of the independence of VaR overdrafts [4]: LR q q q q q ind T T T T T T � � � � � � � 2 1 1 1 00 10 01 11 00 01 01 01 ln ( ) ( ) ( 11 11 10 11) T T q � � � � � � , where q T T T ij ij i i � � 0 1 , q T T T T T T � � � � � 01 11 00 01 10 11 . Here Tij is the number of periods in which It = j if It –1 = i. LRind has also� 2 distri- bution with one degree of freedom. Owing to the fact that LRuc and LRind statis- tics are independent, some authors [6] propose a mixed test LRmix, which takes into account both the number of VaR failures and the time span between those failures: LR LR LRmix uc ind� � . Such statistics have the distribution� 2 with two degrees of freedom. The tests presented here will constitute the basis of the assessment of VaR models further in the paper. In his paper, Jorion also presents the Time Between Failures Test [3]: LR q q q q q v vTBF � � � � � � � � � � � � � � 2 1 1 2 11 1 1 1 1 1 ln ( ) � ( � ) ln ( � � � � � � � � � � � � � � � � � � q q q v i i v i T i i ) � ( � ) 1 1 1 1 1 , � /q vi i�1 , where vi — time between (i – 1) and ith failure.This statistics also has � 2 distri- bution with Ti degree of freedom. The test in which the failures occurring at the time t are independent of ear- lier failures and of the information received at the time t – 1, and of the VaR, is the test proposed by Engel and Manganelli in 2002 (Dynamic Quantile Test (DQ)) [7].With the help of that test, one can identify the «non-acceptable» result of value at risk measurement, defined below, which cannot be eliminated by classical tests of failure number and independence. When VaR value is analyzed VaR with the probability with the proba t q X q X ( ) , � � � 1 bility q � � W. Skrodzka 58 ISSN 0204–3572. Electronic Modeling. 2009. V. 31. ¹ 6 the following regression equation is analyzed: I q q I q q ft i t i p t i p p j t j( ) ( ) ( ) ( , � � � � � � � � � ��0 1 1 1 1 � � � �VaR ) � � � � t j n 1 , where�t j�1, — information given to the investor at the time t – 1. Rejecting the zero hypothesis: H q q 0 0 : � ,�i �0, i p n� � �1 2 1, , ..., means lack of the correct- ness of the VaR model. The DQ test makes it possible to detect any deviations from the independ- ence of the failures described by Markov’s chains of the rank higher than one. Estimating the VaR level with the use of Monte Carlo simulation in con- nection with copula function. In this paper, the level of VaR has been estimated with the use of Monte Carlo simulation in connection with copula function. The definition of copula function as well as the description of its character- istics is presented in detail by Nelsen in his work [8]. In a two-dimensional case which can be generalized onto a multi-dimensional case, the copula function is defined in the following manner. Definition. A two-dimensional function C :[ . ] [ . ]01 01 2 � is called a copula function on condition that it meets the following conditions: C (u, v) is ascending as regards both the variable u and the variable v; C (u, 0) = C (0, v) = 0; C (u, 1) = u; C (1, v) = v; � �u u v v 1 2 1 2 01, , , [ . ] such, that u u 1 2 � and v v 1 2 � , then C u v C u v C u v( , ) ( , ) ( , ) 2 2 2 1 1 2 � � � �C u v( , ) 1 1 0. The calculations have been done for a two-summand portfolio with the risk factors being WIBOR 6M i WIBOR T/N rates of interest. The calculations have been based on the data taken from the inter-bank financial market. The VaR that has been estimated for a two-summand portfolio at the time t has been compared with the actual loss of the portfolio’s value during the period of [t, t + 1]. If the ac- tual loss exceeds the VaR that has been calculated, the so-called failure is ob- tained. 1 The sum of failures for the whole period of time divided by the length of that period of time gives the relative number of failures. In a correctly-working model, the number should more or less equal the level of VaR tolerance. Because of the fact that estimating the parameters of �-stable distributions and of the cop- ula functions was made once every 10 session days (once every two calendar Assessment Methods for Measuring Value at Risk Based on the Hit Function ISSN 0204–3572. Ýëåêòðîí. ìîäåëèðîâàíèå. 2009. Ò. 31. ¹ 6 59 1 Committee on Banking Supervision in Poland (KNB), basing on the number of failures of a 1-day VaR (0.99), observed in the recent 250 days, lays down the spheres of VaR model quality. weeks), the VaR was determined for all methods at the same time. VaR was de- termined at the trust level of 0.95. All calculations have been done with the use of the programme R: Version 2.2.0 1 . In the empirical research, the Bond functions of the Archimedean family have been used. The functions employed include Clayton copula, Frank copula and Gumbel copula. The empirical research has been conducted on the basis of the data simulated by Monte Carlo method. Marginal distributions have been generated with the use of �-stable distributions having the coefficients estimated from historical data. The parameters of stable distributions have been estimated with the use of a programme called STABLE written by J. Nolan ver. 3.04. Also, the method of quantile estimation and the method of greatest plausibility have been used. In the process of estimation as well as in the measurement itself, a movable window was used. That type of action allows for the comparison of the effectiveness of VaR for different methods, but for the same amount of historical data used; 250 mar- ket quotations have been assumed as the length of a movable window. 2 It is the length of the period taken into account by KNB in defining the quality areas of the VaR model for banking institutions. On the basis of 250 market quotations, estimations of two �-stable distributions have been made for a series of rates of return of two selected instruments of the financial market, constituting the sum- mands of the investigated portfolio. In the case when the method of the greatest plausibility has been used, the following assumptions have been made: � > 0.5; when � < 0.8, the method is changed into a quantile-based one; when � � �[0,993; 1] � = 1 is assumed; when ��� [1; 1,007] � = 1.007 is assumed. The assumptions stem from the difficulties of numerical nature that arise during the calculation of the density and the cumulative distribution function of an �-stable distribution both in the case whaen � > 0.5 and when it approaches unity. In the majority of cases, the parameters estimated with the use of particular methods move within the same range of values. The location parameter�, whose values calculated with the use of the quantile method differ as for the sign when compared with the method of greatest plausibility, constitutes an exception. Of some curiosity are also great estimation differences of almost every parameter between the chosen subsamples, which indirectly indicates a change in market mechanisms in particular subperiods. Also, the researchers have observed cer- tain anomalies in the process of estimating � and � parameters with the use of ML method. Such a situation occurs if the value of the estimated parameter � is W. Skrodzka 60 ISSN 0204–3572. Electronic Modeling. 2009. V. 31. ¹ 6 1 The R Foundation for Statistical Computing. — Copyright 2005. ISBN 3-900051-07-0. 2 An average number of quotations per annum. less than 0.8. Then, the process of estimation is broken. In such case, the empiri- cal research has been made with the use of quantile estimation. The estimated value of shape coefficient � turned out to be less than 2, which means the exis- tence of the so-called «thick tails». Those results indicate that using the normal distribution for the empirical approximation of the distribution of rates of return of WIBOR interest rates can lead to the bias of the result. Then, with the use of greatest plausibility method, the parameter � of a cho- sen copula function has been estimated. The parameter has been determined on the basis of Kendal calculated for a pair of rates of return of WIBOR 6M and WIBOR T/N interest rates. When comparing the results for different bond functions, one can note higher values of the � coefficient for the Frank copula bond function. In the next stage, pairs of pseudo-random numbers have been sampled hav- ing the overall distribution determined by the copula function with a pre-esti- mated � parameter and with marginal distributions determined by the estimated parameters of �-stable distributions. The size of the random sample generated with the help of Monte Carlo Method amounted to 10000 two-dimensional quo- Assessment Methods for Measuring Value at Risk Based on the Hit Function ISSN 0204–3572. Ýëåêòðîí. ìîäåëèðîâàíèå. 2009. Ò. 31. ¹ 6 61 2002 2003 2004 2005 2006 1.2 1.1 1.0 0.9 Value at Risk for the portfolio of WIBOR T/N and WIBOR 6M with the risk factors, simulated with the Monte Carlo method with Clayton copula bond function and with stable marginal distri- butions Source: the calculations made by the author with the programme R: Version 2.2.0. VaR Years tations for the portfolio and for each of the bond functions. By applying the for- mula for the rate of return from the portfolio, 10000 simulations of the rate of return from a two-dimensional portfolio have been obtained in each of the subperiods. The estimated VaR has been obtained on the basis of the simulated quantile of the distribution of the rates of return, with the level of trust determined as 0.95. This process has been repeated 95 times for each of the subperiods, created ana- logically to the estimation process. The change of sampling parameters takes place every 10 days. During the process of generating random numbers from a multi-dimensional distribution with the use of copula bond functions, there ap- peared a problem connected with the effectiveness of the calculations. The aver- age time of the calculations connected with a single simulation amounted to 0.2 sec. For the purpose of increasing the effectiveness of the calculation procedure, cubic splins have been applied. Figure presents a sample simulation using Monte Carlo method with Clay- ton copula bond function and with stable marginal distributions of the VaR in particular subperiods for WIBOR T/N and for WIBOR 6M. The circles present actual values of the portfolio calculated on the basis of empirical data. The black line stands for the VaR level estimated with the help of a simulation. The circles below the line stand for the failures of the simulated VaR. Monte Carlo simulation method coupled with Clayton copula bond func- tion, Frank copula and Gumbel copula for pairs of rates of return of WIBOR T/N and WIBOR 6M interest rates gave similar result in the case of stable marginal distributions. Verifying the quality of the adopted models for the measurement of the VaR — back-testing. On the basis of Monte Carlo simulation methods pre- sented above coupled with the copula bond function and on the basis of classical methods of measurement, we were able to calculate the VaR in particular subperiods, identify the instances of failures and determine the value of the test of the number of failures and their independence. Table presents the results of empirical research as the values of the appropriate test statistics, for the pairs of rates of return of WIBOR T/N and WIBOR 6M interest rates, for particular methods of VaR calculation and with the tolerance level of 0.05. In Table below, the first column shows the methods of VaR measurement that have been taken into account in the research. The remaining columns pres- ent the values of the statistics for Kupiec test, Christoffersen test and for the mixed test. The values of the empirical statistics in bold stand for the cases in which we have to reject the zero hypothesis of the correctness of the VaR model. Furthermore, on the basis of Kupiec test we can claim that for the size of the sam- ple amounting to T = 950, for the VaR tolerance level amounting to 0.05 and for the relevance level of the test amounting to 0.05, the range of the number of fail- W. Skrodzka 62 ISSN 0204–3572. Electronic Modeling. 2009. V. 31. ¹ 6 ures determining the non-critical area 1 equals [35; 61] with the expected value of the number of failures amounting to 48. The underlined italics indicate the best results that have been obtained. For the investigated portfolio with the risk factors being the WIBOR T/N and WIBOR 6M rates of interest, Monte Carlo simulation methods using copula functions based on stable distributions gave similar results, approaching the value of the expected number of failures. The best result was obtained for Monte Carlo simulation with Clayton copula bond function and with stable mar- ginal distributions. It means that within a given method the lowest result has been obtained from the failures statistics tests and their independence, and from the mixed test. In the table presented above, those results have been italicized and underlined. Correct results have also been obtained with the use of historical simulation. In the case of variance-covariance method, the results obtained diverge signifi- cantly from the expected number of failures. Those methods have noticeably in- creased the value of the VaR parameter, and because of that, the number of fail- ures was significantly lower than the expected one. This might be explained by the fact that the assumption of normal distributions of rates of return has been made in the situation when empirical distributions have much «thicker tails». That is a very important observation from the point of interest rate risk measure- ment. Using stable distributions as marginal distributions allows one to get better results. Assessment Methods for Measuring Value at Risk Based on the Hit Function ISSN 0204–3572. Ýëåêòðîí. ìîäåëèðîâàíèå. 2009. Ò. 31. ¹ 6 63 Method Number of failures Relative number of failures LRuc LRind LRmix Historical simulation 45 0.0474 0.140869 0.00943 0.150299 Variance-covariance method 29 0.0305 8.757494 0.014963 8.772458 Monte Carlo simulation: Gumbel copula; marginal distributions stable 43 0.0453 0.462855 0.607275 1.07013 Monte Carlo simulation: Frank copula; marginal distributions stable 49 0.0516 0.049372 0.092143 0.141515 Monte Carlo simulation: Clayton copula; marginal distributions stable 47 0.0495 0.005559 0.053392 0.05895 Source: the calculations made by the author with the programme R: Version 2.2.0. The values of test statistics for the rates of return of WIBOR T/N and WIBOR 6M interest rates 1 The area of the assumption of the model correctness hypothesis. Conclusions. In the paper we have compared the classical approach to- wards the calculation of the VaR: with the use of historical simulation and with the use of variance-covariance method with a much more complicated method of determining the unknown quantile of a certain combined distribution with the use of Monte Carlo simulation with copula bond function. Such a method gives many possibilities of choosing the marginal distributions of the same or of dif- ferent types. In this paper the author has used �-stable distributions, which, due to their properties better fit the empirical data than the normal distributions. In order to compare particular methods of VaR measurement, the back-test- ing procedure has been applied. The results of the failure test that have been ob- tained confirmed the effectiveness of Monte Carlo methods with copula bond function and with �-stable distribution when it comes to measuring the risk of the rates of interest. The methodology of assessing the effectiveness of VaR measurement is quite wide. The methods presented in the paper are the most popular ones. They are not, however, free from drawbacks. The classical tests are characterized by low power. Their undeniable merit is, however, their simplicity and intuitive in- terpretation corresponding to the very definition of the VaR and to VaR failures. Çàïðîïîíîâàíî ñïîñîáè óïðàâë³ííÿ ô³íàíñîâèìè ðèçèêàìè. Çâîðîòíº òåñòóâàííÿ — íåîá- õ³äíà ïðîöåäóðà äëÿ âèáîðó òà îö³íêè ïðèäàòíîñò³ ìîäåëåé îö³íþâàííÿ ðèçèê³â. Íàâåäåíî äåÿê³ òèïîâ³ ñòàòèñòè÷í³ ìåòîäè áàçîâàí³ íà ôóíêö³¿ çá³ãó. Ïîêàçàíî ïåðåâàãè òà íåäîë³êè öèõ ìåòîä³â. Îêðåìó óâàãó ïðèä³ëåíî ìîäåëþâàííþ ìåòîäîì Ìîíòå-Êàðëî, à òàêîæ ôóíêö³¿ çâ’ÿçêè ó ìåòîäîëî㳿 îö³íêè âåëè÷èíè ðèçèê³â. 1. Jajuga K. Metody Ekonometryczne i Statystyczne w Analizie Rynku Kapita owego. — Wroclaw: AE, 2000. 2. Best P. Warto nara�zona na ryzyko. Obliczanie i wdra anie modelu VaR.— Krakow: Dom Wydawniczy ABC, 2000. 3. Jorion P. Value at Risk. 2 nd edition. — New Jersey: McGraw-Hill, 2001. 4. Christoffersen P. Evaluating Interval Forecasts // International Economic Review.— 1998. — 39. 5. Kupiec P. Techniques for Verifying the Accuracy of Risk Management Models//J. of Derivatives. — 1995. — 2. 6. Piontek K. A Survey and a Comparison of Back Testing Procedures. / In P. Chrzan, Matematyczne i Ekonometryczne Metody Oceny Ryzyka Finansowego/ Prace Naukowe AE w Katowicach. — Katowice, 2007. 7. Sarma M., Thomas S., Shah A. Selection of Value-at-Risk Models, 2003. — ideas.repec.org/ s/jof/jforec.html 8. Nelsen R. B. An Introduction to Copulas. — N Y: Springer Verlag, 1999. 9. Piontek K. Wykorzystanie wielorownaniowych modeli AR-GARCH w pomiarze ryzyka metod VaR, Modelowanie preferencji a ryzyko/Prace Naukowe AE w Katowicach. — Katowice, 2005. Submitted on 25.08.09 W. Skrodzka 64 ISSN 0204–3572. Electronic Modeling. 2009. V. 31. ¹ 6
id nasplib_isofts_kiev_ua-123456789-101528
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 0204-3572
language English
last_indexed 2025-12-07T18:09:39Z
publishDate 2009
publisher Інститут проблем моделювання в енергетиці ім. Г.Є. Пухова НАН України
record_format dspace
spelling Skrodzka, W.
2016-06-04T13:15:30Z
2016-06-04T13:15:30Z
2009
Assessment Methods for Measuring Value at Risk Based on the Hit Function / W. Skrodzka // Электронное моделирование. — 2009. — Т. 31, № 6. — С. 55-64. — Бібліогр.: 9 назв. — англ.
0204-3572
https://nasplib.isofts.kiev.ua/handle/123456789/101528
The aim of this paper is to provide tools to aid the management process of Financial Risk. Backtesting is the necessary procedure to choose and to evaluate the stability of a value at risk (VaR) models. This paper presents some typical, statistical methods based on the hit function. Advantages and disadvantages of those methods are discussed in this paper. In the proposed approach to risk measurement, special attention is paid to the use of the Monte Carlo simulation along with the copula relation function in VaR methodology.
Предложены средства управления финансовыми рисками. Обратное тестирование — необходимая процедура при выборе и оценивании пригодности моделей оценки риска. Представлены некоторые типичные статистические методы на основе функции совпадения. Описаны преимущества и недостатки этих методов. В предложенном подходе к управлению рисками особое внимание уделено моделированию методом Монте-Карло, а также функции связки в методологии оценки величины рисков.
Запропоновано способи управління фінансовими ризиками. Зворотнє тестування — необхідна процедура для вибору та оцінки придатності моделей оцінювання ризиків. Наведено деякі типові статистичні методи базовані на функції збігу. Показано переваги та недоліки цих методів. Окрему увагу приділено моделюванню методом Монте-Карло, а також функції зв’язки у методології оцінки величини ризиків.
en
Інститут проблем моделювання в енергетиці ім. Г.Є. Пухова НАН України
Электронное моделирование
Assessment Methods for Measuring Value at Risk Based on the Hit Function
Методы оценки для измерения цены риска на основе функции попадания
Article
published earlier
spellingShingle Assessment Methods for Measuring Value at Risk Based on the Hit Function
Skrodzka, W.
title Assessment Methods for Measuring Value at Risk Based on the Hit Function
title_alt Методы оценки для измерения цены риска на основе функции попадания
title_full Assessment Methods for Measuring Value at Risk Based on the Hit Function
title_fullStr Assessment Methods for Measuring Value at Risk Based on the Hit Function
title_full_unstemmed Assessment Methods for Measuring Value at Risk Based on the Hit Function
title_short Assessment Methods for Measuring Value at Risk Based on the Hit Function
title_sort assessment methods for measuring value at risk based on the hit function
url https://nasplib.isofts.kiev.ua/handle/123456789/101528
work_keys_str_mv AT skrodzkaw assessmentmethodsformeasuringvalueatriskbasedonthehitfunction
AT skrodzkaw metodyocenkidlâizmereniâcenyriskanaosnovefunkciipopadaniâ