×

Estimating a gradual parameter change in an AR(1)-process. (English) Zbl 07575564

Summary: We discuss the estimation of a change-point \(t_0\) at which the parameter of a (non-stationary) AR(1)-process possibly changes in a gradual way. Making use of the observations \(X_1,\ldots, X_n\), we shall study the least squares estimator \(\widehat{t_0}\) for \(t_0\), which is obtained by minimizing the sum of squares of residuals with respect to the given parameters. As a first result it can be shown that, under certain regularity and moment assumptions, \(\widehat{t_0} /n\) is a consistent estimator for \(\tau_0\), where \(t_0 =\lfloor n\tau_0 \rfloor\), with \(0<\tau_0 <1\), i.e., \(\widehat{t_0} /n \,\overset{P}{\rightarrow}\,\tau_0 (n\rightarrow \infty)\). Based on the rates obtained in the proof of the consistency result, a first, but rough, convergence rate statement can immediately be given. Under somewhat stronger assumptions, a precise rate can be derived via the asymptotic normality of our estimator. Some results from a small simulation study are included to give an idea of the finite sample behaviour of the proposed estimator.

MSC:

62F10 Point estimation
62F12 Asymptotic properties of parametric estimators
62M10 Time series, auto-correlation, regression, etc. in statistics (GARCH)

References:

[1] Albin, JMP; Jarušková, D., On a test statistic for linear trend, Extremes, 6, 247-258 (2003) · Zbl 1050.62085 · doi:10.1023/B:EXTR.0000031181.16968.17
[2] Aue, A.; Horváth, L., Structural breaks in time series, J Time Ser Anal, 34, 1-16 (2013) · Zbl 1274.62553 · doi:10.1111/j.1467-9892.2012.00819.x
[3] Aue, A.; Steinebach, J., A note on estimating the change-point of a gradually changing stochastic process, Stat Probab Lett, 56, 177-191 (2002) · Zbl 1065.62149 · doi:10.1016/S0167-7152(01)00184-5
[4] Bai, J., Least squares estimation of a shift in linear processes, J Time Ser Anal, 15, 453-472 (1994) · Zbl 0808.62079 · doi:10.1111/j.1467-9892.1994.tb00204.x
[5] Bai, J., Vector autoregressive models with structural changes in regression coefficients and in variance-covariance matrices, Ann Econom Finance, 1, 303-339 (2000)
[6] Billingsley, P., Convergence of probability measures (1968), New York: Wiley, New York · Zbl 0172.21201
[7] Davidson, D., Stochastic limit theory (1994), Oxford: Oxford University Press, Oxford · Zbl 0904.60002 · doi:10.1093/0198774036.001.0001
[8] Davis, RA; Huang, D.; Yao, YC, Testing for a change in the parameter value and order of an autoregressive model, Ann Stat, 23, 282-304 (1995) · Zbl 0822.62072 · doi:10.1214/aos/1176324468
[9] Döring M (2015a) Asymmetric cusp estimation in regression models. Statistics 49:1279-1297 · Zbl 1337.62151
[10] Döring M (2015b) Rate of convergence of a change point estimator in a misspecified regression model. In: A. Steland, E. Rafajłowicz, K. Szajowski (eds.) Stochastic Models, Statistics and Their Applications (Wrocław, 2015), Springer Proc. Math. Statist., vol. 122, pp. 49-55. Springer, Cham · Zbl 1349.62057
[11] Döring, M.; Jensen, U., Smooth change point estimation in regression models with random design, Ann Inst Stat Math, 67, 595-619 (2015) · Zbl 1440.62128 · doi:10.1007/s10463-014-0467-8
[12] Dümbgen, L., The asymptotic behavior of some nonparametric change-point estimators, Ann Stat, 19, 1471-1495 (1991) · Zbl 0776.62032 · doi:10.1214/aos/1176348257
[13] Dvořák M (2015) Stability in Autoregressive Time Series Models. Ph.D. thesis, Charles University, Prague
[14] Gombay, E., Change detection in autoregressive time series, J Multiv Anal, 99, 451-464 (2008) · Zbl 1148.62069 · doi:10.1016/j.jmva.2007.01.003
[15] He, C.; Teräsvirta, T.; González, A., Testing parameter constancy in stationary vector autoregressive models against continuous change, Econom Rev, 28, 225-245 (2008) · Zbl 1156.62056 · doi:10.1080/07474930802388041
[16] Hlávka, Z.; Hušková, M., Two-sample gradual change analysis, Revstat, 15, 355-372 (2017) · Zbl 1373.62084
[17] Hoffmann, M.; Dette, H., On detecting changes in the jumps of arbitrary size of a time-continuous stochastic process, Electr J Stat, 13, 3654-3709 (2019) · Zbl 1466.60070
[18] Hoffmann, M.; Vetter, M.; Dette, H., Nonparametric inference of gradual changes in the jump behaviour of time-continuous processes, Stoch Process Appl, 128, 3679-3723 (2018) · Zbl 1401.60053 · doi:10.1016/j.spa.2017.12.005
[19] Horváth, L., Change in autoregressive processes, Stoch Process Appl, 44, 221-242 (1993) · Zbl 0769.62067 · doi:10.1016/0304-4149(93)90026-Z
[20] Hušková M (1998a) Estimators in the location model with gradual changes. Comment Math Univ Carolin 39:147-157 · Zbl 0953.62020
[21] Hušková M (1998b) Remarks on test procedures for gradual changes. In: Szyszkowicz B (ed) Asymptotic methods in probability and statistics (Ottawa, 1997). North-Holland, Amsterdam, pp. 577-583 · Zbl 0945.62023
[22] Hušková, M., Gradual changes versus abrupt changes, J Statist Plann Infer, 76, 109-125 (1999) · Zbl 1054.62520 · doi:10.1016/S0378-3758(98)00173-6
[23] Hušková M (2001) A note on estimators of gradual changes. In: M. de Gunst, C. Klaassen, A. van der Vaart (eds.) State of the Art in Probability and Statistics (Leiden, 1999), IMS Lecture Notes Monogr. Ser., vol. 36, pp. 345-358. Institute of Mathematical Statistics, Beachwood, OH · Zbl 1373.62208
[24] Hušková M, Kirch C, Prášková Z, Steinebach J (2008) On the detection of changes in autoregressive time series. II. Resampling procedures. J Stat Plann Infer 138:1697-1721 · Zbl 1131.62079
[25] Hušková, M.; Prášková, Z.; Steinebach, J., On the detection of changes in autoregressive time series. I. Asymptotics, J Stat Plann Infer, 137, 1243-1259 (2007) · Zbl 1107.62090 · doi:10.1016/j.jspi.2006.02.010
[26] Hušková, M.; Steinebach, J., Limit theorems for a class of tests of gradual changes, J Stat Plann Infer, 89, 57-77 (2000) · Zbl 0998.62010 · doi:10.1016/S0378-3758(00)00094-X
[27] Hušková, M.; Steinebach, J., Asymptotic tests for gradual changes, Stat Decis, 20, 137-151 (2002) · Zbl 0997.62017
[28] Jarušková D (1998a) Change-point estimator in gradually changing sequences. Comment Math Univ Carolin 39:551-561 · Zbl 0962.62019
[29] Jarušková D (1998b) Testing appearance of linear trend. J Stat Plann Infer 70:263-276 · Zbl 0938.62071
[30] Jarušková, D., Testing appearance of polynomial trend, Extremes, 2, 25-37 (1999) · Zbl 0938.62096 · doi:10.1023/A:1009951807623
[31] Jarušková, D., Change-point estimator in continuous quadratic regression, Comment Math Univ Carolin, 42, 741-752 (2001) · Zbl 1091.62506
[32] Jarušková, D., Change in polynomial regression and related processes, Theory Stoch Process, 8, 162-168 (2002) · Zbl 1022.62079
[33] Jarušková, D., Asymptotic distribution of a statistic testing a change in simple linear regression with equidistant design, Stat Probab Lett, 64, 89-95 (2003) · Zbl 1113.62305 · doi:10.1016/S0167-7152(03)00143-3
[34] Kirch, C.; Muhsal, B.; Ombao, H., Detection of changes in multivariate time series with application to EEG data, J Am Stat Assoc, 110, 1197-1216 (2015) · Zbl 1378.62072 · doi:10.1080/01621459.2014.957545
[35] Kirch, C.; Steinebach, J., Permutation principles for the change analysis of stochastic processes under strong invariance, J Comput Appl Math, 186, 64-88 (2006) · Zbl 1074.62030 · doi:10.1016/j.cam.2005.03.065
[36] Picard, D., Testing and estimating change-points in time series, Adv Appl Probab, 17, 841-867 (1985) · Zbl 0585.62151 · doi:10.2307/1427090
[37] Quessy, JF, Consistent nonparametric tests for detecting gradual changes in the marginals and the copula of multivariate time series, Stat Papers, 60, 717-746 (2019) · Zbl 1419.62244 · doi:10.1007/s00362-016-0846-8
[38] Račkauskas A, Tamulis A (2013) Modeling of gradual epidemic changes. Liet Mat Rink, Proc Lith Math Soc, Ser A 54:55-60 · Zbl 1369.92128
[39] Salazar, D., Structural changes in time series models, J Econom, 19, 147-163 (1982) · Zbl 0491.62079 · doi:10.1016/0304-4076(82)90055-0
[40] Slabý, A., Limit theorems for rank statistics detecting gradual changes, Comment Math Univ Carolin, 42, 591-600 (2001) · Zbl 1053.62056
[41] Slama, A.; Saggou, H., A Bayesian analysis of a change in the parameters of autoregressive time series, Comm Stat Simul Comput, 46, 7008-7021 (2017) · Zbl 1462.62551 · doi:10.1080/03610918.2016.1222423
[42] Steinebach, J., Some remarks on the testing of smooth changes in the linear drift of a stochastic process, Theory Probab Math Stat, 61, 173-185 (2000) · Zbl 0980.62076
[43] Steinebach, J.; Timmermann, H., Sequential testing of gradual changes in the drift of a stochastic process, J Stat Plann Infer, 141, 2682-2699 (2011) · Zbl 1213.62129 · doi:10.1016/j.jspi.2011.02.020
[44] Timmermann H (2014) Monitoring Procedures for Detecting Gradual Changes. Ph.D. thesis, University of Cologne · Zbl 1302.62004
[45] Timmermann, H., Sequential detection of gradual changes in the location of a general stochastic process, Stat Probab Lett, 99, 85-93 (2015) · Zbl 1328.60107 · doi:10.1016/j.spl.2015.01.001
[46] Venkatesan, D.; Arumugam, P., Bayesian analysis of structural changes in autoregressive models, Am J Math Manag Sci, 27, 153-162 (2007) · Zbl 1141.62017
[47] Vogt, M.; Dette, H., Detecting gradual changes in locally stationary processes, Ann Stat, 43, 713-740 (2015) · Zbl 1312.62045 · doi:10.1214/14-AOS1297
[48] Wang, L., Gradual changes in long memory processes with applications, Statistics, 41, 221-240 (2007) · Zbl 1116.62098 · doi:10.1080/02331880701223555
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.