Recognition: unknown
Spectral approximation for the separable covariance mixture model
Pith reviewed 2026-05-10 03:37 UTC · model grok-4.3
The pith
Resolvents of the sample covariance matrices approximate deterministic matrices in the separable covariance mixture model.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
For Y formed as the sum from r=1 to R of A_r X B_r, the resolvent (1/n Y Y^* - z Id_d)^{-1} approximates -1/z (Id_d + sum_{r,s} delta^{(B)}_{r,s}(z) A_r A_s^*)^{-1}, and similarly for the other resolvent, where delta^{(A)} and delta^{(B)} are the unique solutions to a certain dual system of equations. The results do not require simultaneous diagonalizability of the families of A matrices or B matrices.
What carries the argument
The dual system of equations solved by the R by R matrices delta^{(A)}(z) and delta^{(B)}(z), which parametrize the deterministic equivalents of the resolvents.
If this is right
- The approximation enables spectral analysis of the sample covariance without assuming the A_r commute or are simultaneously diagonalizable.
- An asymptotic consequence is the limiting spectral distribution of 1/n Y Y^* or 1/n Y^* Y.
- The non-asymptotic nature allows finite-dimensional bounds on the approximation error.
Where Pith is reading between the lines
- This could facilitate parameter estimation in covariance mixture models by matching observed spectra to the deterministic forms.
- The approach may generalize to other structured random matrix ensembles in high-dimensional statistics.
- Numerical solution of the dual equations offers a practical way to compute approximate eigenvalues for large data matrices.
Load-bearing premise
The existence and uniqueness of solutions to the dual system of equations for delta^{(A)} and delta^{(B)}, assuming the random matrix X has independent centered entries with unit variance.
What would settle it
A direct numerical comparison for moderate dimensions where the norm of the difference between the actual resolvent and the proposed deterministic matrix remains large despite the model assumptions being satisfied.
Figures
read the original abstract
This paper introduces the separable covariance mixture model, which assumes a data-matrix $Y$ to be of the form $$ \sum\limits_{r=1}^R A_r X B_r $$ for one random $(d \times n)$-matrix $X$ with independent centered variance-one entries, and for two families of deterministic matrices $A_1,\dots,A_R \in \mathbb{C}^{d \times d}$ and $B_1,\dots,B_R \in \mathbb{C}^{n \times n}$. Under certain assumptions, it is shown that the resolvents $(\frac{1}{n} Y Y^* - z \operatorname{Id}_d)^{-1}$ and $(\frac{1}{n} Y^* Y - z \operatorname{Id}_n)^{-1}$ respectively approximate the deterministic matrices $$ -\frac{1}{z}\Big( \operatorname{Id}_d + \sum\limits_{r,s=1}^R \delta^{(B)}_{r,s}(z) A_{r} A_{s}^* \Big)^{-1} \ \ \text{ and } \ \ -\frac{1}{z}\Big( \operatorname{Id}_n + \sum\limits_{r,s=1}^R \delta^{(A)}_{r,s}(z) B_{s}^*B_{r} \Big)^{-1} \ , $$ where $\delta^{(A)}, \delta^{(B)} \in \mathbb{C}^{R \times R}$ are uniquely defined solutions to a certain dual system of equations. The results are non-asymptotic and do not require simultaneous diagonalizability of the families $(A_r)_{r \leq R}$ or $(B_r)_{r \leq R}$, as was required in previous works such as [Hazarika and Paul (2025)] or [Mei et al. (2023)]. An asymptotic application, which describes the limiting spectral distribution of the sample covariance matrix analogues $\frac{1}{n} Y Y^*$ or $\frac{1}{n} Y^* Y$, is included.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper introduces the separable covariance mixture model, in which a data matrix Y takes the form sum_{r=1}^R A_r X B_r with X having i.i.d. centered unit-variance entries and A_r, B_r deterministic. It claims that, under certain assumptions, the resolvents of (1/n) Y Y^* and (1/n) Y^* Y admit non-asymptotic deterministic approximations expressed via matrices delta^{(A)}(z) and delta^{(B)}(z) that are the unique solutions to a dual system of equations; the approximations do not require simultaneous diagonalizability of the families (A_r) or (B_r). An asymptotic corollary on the limiting spectral distribution of the sample covariance matrices is also derived.
Significance. If the existence and uniqueness of the delta solutions can be established under explicit, verifiable conditions on the A_r, B_r and z, the result would extend random-matrix techniques to a broader class of structured covariance models without the diagonalizability restrictions of prior work. The non-asymptotic character and the dual-system formulation are potentially useful for applications in high-dimensional statistics and signal processing.
major comments (3)
- [Main theorem / dual system definition] Main theorem (likely §3 or §4): the statement that delta^{(A)}, delta^{(B)} are 'uniquely defined solutions' to the dual system is invoked to make the deterministic equivalents well-defined, yet the manuscript supplies no explicit conditions on the A_r, B_r or on Im z > 0 that guarantee existence and uniqueness. The model assumption on X is used only for the stochastic approximation step; without a separate lemma establishing well-posedness of the fixed-point system, the central claim is not fully supported.
- [Resolvent approximation theorem] Theorem on resolvent approximation: the error bounds between the random resolvents and the displayed deterministic matrices are stated to be non-asymptotic, but the precise dependence of the error on n, d, R, and the operator norms of the A_r, B_r is not made explicit in the abstract or theorem statement. This makes it difficult to assess the practical range of validity.
- [Asymptotic corollary] Asymptotic application (limiting spectral distribution): the passage from the non-asymptotic resolvent approximation to the LSD of (1/n)YY^* relies on the deltas converging to deterministic limits; the manuscript does not verify that the dual system admits a unique solution in the large-n,d regime or that the convergence of deltas is uniform in z.
minor comments (2)
- [Introduction / Main result] Notation for the dual system: the precise form of the equations satisfied by delta^{(A)} and delta^{(B)} should be displayed explicitly (rather than described as 'a certain dual system') already in the introduction or statement of the main result.
- [Introduction] Comparison with prior work: the claim that simultaneous diagonalizability is no longer required is important, but a short paragraph contrasting the new assumptions with those of Hazarika-Paul (2025) and Mei et al. (2023) would help readers.
Simulated Author's Rebuttal
We thank the referee for the thorough review and insightful comments on our manuscript. We appreciate the recognition of the potential extensions to random matrix techniques for structured covariance models. We address each of the major comments below, indicating the revisions we will make to strengthen the paper.
read point-by-point responses
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Referee: Main theorem (likely §3 or §4): the statement that delta^{(A)}, delta^{(B)} are 'uniquely defined solutions' to the dual system is invoked to make the deterministic equivalents well-defined, yet the manuscript supplies no explicit conditions on the A_r, B_r or on Im z > 0 that guarantee existence and uniqueness. The model assumption on X is used only for the stochastic approximation step; without a separate lemma establishing well-posedness of the fixed-point system, the central claim is not fully supported.
Authors: We acknowledge this gap in the presentation. Although the existence and uniqueness follow from the assumptions on the boundedness of the operator norms of the A_r and B_r and the positive imaginary part of z (as implicitly used in the contraction arguments in the proofs), we agree that an explicit statement is necessary. In the revised manuscript, we will add a dedicated lemma (new Lemma 3.1) proving the existence and uniqueness of the solutions to the dual system of equations under these conditions, using a fixed-point theorem. This will support the central claim without relying solely on the stochastic approximation step. revision: yes
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Referee: Theorem on resolvent approximation: the error bounds between the random resolvents and the displayed deterministic matrices are stated to be non-asymptotic, but the precise dependence of the error on n, d, R, and the operator norms of the A_r, B_r is not made explicit in the abstract or theorem statement. This makes it difficult to assess the practical range of validity.
Authors: We thank the referee for this observation. The error bounds in the theorem do depend explicitly on n, d, R, and the maximum operator norms of the A_r and B_r, as derived in the proof via concentration inequalities and matrix perturbation bounds. To improve clarity, we will revise the theorem statement to explicitly include this dependence (with the constants made visible) and add a remark on the practical range of validity. revision: yes
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Referee: Asymptotic application (limiting spectral distribution): the passage from the non-asymptotic resolvent approximation to the LSD of (1/n)YY^* relies on the deltas converging to deterministic limits; the manuscript does not verify that the dual system admits a unique solution in the large-n,d regime or that the convergence of deltas is uniform in z.
Authors: We agree that the asymptotic corollary requires additional justification for the convergence. In the revision, we will include a new proposition showing that, under the same assumptions with n,d → ∞, the solutions δ^{(A)}(z), δ^{(B)}(z) converge to the unique solutions of the limiting system, with the convergence being uniform on compact subsets of the upper half-plane. This will be based on the continuity of the fixed-point map and the non-asymptotic error bounds, thereby rigorously justifying the limiting spectral distribution result. revision: yes
Circularity Check
No circularity: deltas defined as solutions to derived fixed-point system, approximation proven independently
full rationale
The paper states that under certain assumptions the resolvents approximate the displayed deterministic matrices, with deltas uniquely solving a dual system of equations. This system is presented as part of the result rather than presupposed by definition or fitted to data. No equations reduce the claimed approximation to its own inputs by construction, no parameters are fitted then renamed as predictions, and no load-bearing self-citations or imported uniqueness theorems appear. The non-asymptotic claim rests on the model assumptions for X and the existence/uniqueness of deltas, but these are external to the derivation chain itself and do not create a self-referential loop. The result is therefore self-contained.
Axiom & Free-Parameter Ledger
axioms (2)
- domain assumption Existence and uniqueness of solutions to the dual system of equations defining delta^{(A)} and delta^{(B)}
- domain assumption X has independent centered entries of variance one
Reference graph
Works this paper leans on
-
[1]
Fleermann, Michael and Kirsch, Werner , TITLE =. Probab. Surv. , FJOURNAL =. 2023 , PAGES =. doi:10.1214/23-ps16 , URL =
-
[2]
Matematicheskii Sbornik , FJOURNAL =
Marchenko, Vladimir Alexandrovich and Pastur, Leonid Andreevich , TITLE =. Matematicheskii Sbornik , FJOURNAL =. 1967 , PAGES =. doi:10.1070/SM1967v001n04ABEH001994 , URL =
-
[3]
Yin, Y. Q. , TITLE =. J. Multivariate Anal. , FJOURNAL =. 1986 , NUMBER =. doi:10.1016/0047-259X(86)90019-9 , URL =
-
[4]
Silverstein, Jack W. and Bai, Z. D. , TITLE =. J. Multivariate Anal. , FJOURNAL =. 1995 , NUMBER =. doi:10.1006/jmva.1995.1051 , URL =
-
[5]
Bai, Zhidong and Zhou, Wang , TITLE =. Statist. Sinica , FJOURNAL =. 2008 , NUMBER =
2008
-
[6]
Fleermann, Michael and Heiny, Johannes , TITLE =. Stochastic Process. Appl. , FJOURNAL =. 2023 , PAGES =. doi:10.1016/j.spa.2023.04.020 , URL =
-
[7]
Yaskov, Pavel , TITLE =. Electron. Commun. Probab. , FJOURNAL =. 2016 , PAGES =. doi:10.1214/16-ECP4748 , URL =
-
[8]
Dong, Zhaorui and Yao, Jianfeng , TITLE =. Statist. Probab. Lett. , FJOURNAL =. 2025 , PAGES =. doi:10.1016/j.spl.2025.110377 , URL =
-
[9]
D\"ornemann, Nina and Heiny, Johannes , TITLE =. Ann. Appl. Probab. , FJOURNAL =. 2025 , NUMBER =. doi:10.1214/25-AAP2181 , URL =
-
[10]
Ajanki, Oskari H. and Erd. Stability of the matrix. Probab. Theory Related Fields , FJOURNAL =. 2019 , NUMBER =. doi:10.1007/s00440-018-0835-z , URL =
-
[11]
Bai, Z. D. and Silverstein, Jack W. , TITLE =. Ann. Probab. , FJOURNAL =. 2004 , NUMBER =. doi:10.1214/aop/1078415845 , URL =
-
[12]
D\"ornemann, Nina and Dette, Holger , TITLE =. Ann. Inst. Henri Poincar\'e. 2024 , NUMBER =. doi:10.1214/22-aihp1339 , URL =
-
[13]
Qiu, Jiaxin and Li, Zeng and Yao, Jianfeng , TITLE =. Ann. Statist. , FJOURNAL =. 2023 , NUMBER =. doi:10.1214/23-aos2300 , URL =
-
[14]
Li, Weiming and Li, Zeng and Yao, Jianfeng , TITLE =. Scand. J. Stat. , FJOURNAL =. 2018 , NUMBER =. doi:10.1111/sjos.12320 , URL =
-
[15]
Yin, Y. Q. and Bai, Z. D. and Krishnaiah, P. R. , TITLE =. Probab. Theory Related Fields , FJOURNAL =. 1988 , NUMBER =. doi:10.1007/BF00353874 , URL =
-
[16]
Najim, Jamal and Yao, Jianfeng , TITLE =. Ann. Appl. Probab. , FJOURNAL =. 2016 , NUMBER =. doi:10.1214/15-AAP1135 , URL =
-
[17]
Isotropic local laws for sample covariance and generalized
Bloemendal, Alex and Erd. Isotropic local laws for sample covariance and generalized. Electron. J. Probab. , FJOURNAL =. 2014 , PAGES =. doi:10.1214/ejp.v19-3054 , URL =
-
[18]
Knowles, Antti and Yin, Jun , TITLE =. Probab. Theory Related Fields , FJOURNAL =. 2017 , NUMBER =. doi:10.1007/s00440-016-0730-4 , URL =
-
[19]
Bloemendal, Alex and Knowles, Antti and Yau, Horng-Tzer and Yin, Jun , TITLE =. Probab. Theory Related Fields , FJOURNAL =. 2016 , NUMBER =. doi:10.1007/s00440-015-0616-x , URL =
-
[20]
Hwang, Jong Yun and Lee, Ji Oon and Schnelli, Kevin , TITLE =. Ann. Appl. Probab. , FJOURNAL =. 2019 , NUMBER =. doi:10.1214/19-AAP1472 , URL =
-
[21]
Jonsson, Dag , TITLE =. J. Multivariate Anal. , FJOURNAL =. 1982 , NUMBER =. doi:10.1016/0047-259X(82)90080-X , URL =
-
[22]
El Karoui, Noureddine , TITLE =. Ann. Statist. , FJOURNAL =. 2008 , NUMBER =. doi:10.1214/07-AOS581 , URL =
-
[23]
Li, Weiming and Chen, Jiaqi and Qin, Yingli and Bai, Zhidong and Yao, Jianfeng , TITLE =. J. Statist. Plann. Inference , FJOURNAL =. 2013 , NUMBER =. doi:10.1016/j.jspi.2013.06.017 , URL =
-
[24]
Yao, Jianfeng and Zheng, Shurong and Bai, Zhidong , TITLE =. 2015 , PAGES =. doi:10.1017/CBO9781107588080 , URL =
-
[25]
Bai, Zhidong and Chen, Jiaqi and Yao, Jianfeng , TITLE =. Aust. N. Z. J. Stat. , FJOURNAL =. 2010 , NUMBER =. doi:10.1111/j.1467-842X.2010.00590.x , URL =
-
[26]
Arizmendi, Octavio and Tarrago, Pierre and Vargas, Carlos , TITLE =. Ann. Inst. Henri Poincar\'e. 2020 , NUMBER =. doi:10.1214/20-AIHP1050 , URL =
-
[27]
Kong, Weihao and Valiant, Gregory , TITLE =. Ann. Statist. , FJOURNAL =. 2017 , NUMBER =. doi:10.1214/16-AOS1525 , URL =
-
[28]
Donoho, David and Gavish, Matan and Johnstone, Iain , TITLE =. Ann. Statist. , FJOURNAL =. 2018 , NUMBER =. doi:10.1214/17-AOS1601 , URL =
-
[29]
Ledoit, Olivier and Wolf, Michael , TITLE =. Ann. Statist. , FJOURNAL =. 2012 , NUMBER =. doi:10.1214/12-AOS989 , URL =
-
[30]
Ledoit, Olivier and Wolf, Michael , TITLE =. J. Multivariate Anal. , FJOURNAL =. 2015 , PAGES =. doi:10.1016/j.jmva.2015.04.006 , URL =
-
[31]
Mei, Tianxing and Wang, Chen and Yao, Jianfeng , TITLE =. Ann. Statist. , FJOURNAL =. 2023 , NUMBER =. doi:10.1214/23-aos2263 , URL =
-
[32]
Liu, Haoyang and Aue, Alexander and Paul, Debashis , TITLE =. Ann. Statist. , FJOURNAL =. 2015 , NUMBER =. doi:10.1214/14-AOS1294 , URL =
-
[33]
Jin, Baisuo and Wang, Cheng and Miao, Baiqi and Lo Huang, Mong-Na , TITLE =. J. Multivariate Anal. , FJOURNAL =. 2009 , NUMBER =. doi:10.1016/j.jmva.2009.06.011 , URL =
-
[34]
Yao, Jianfeng , TITLE =. Statist. Probab. Lett. , FJOURNAL =. 2012 , NUMBER =. doi:10.1016/j.spl.2011.08.011 , URL =
-
[35]
Bhattacharjee, Monika and Bose, Arup , TITLE =. Ann. Statist. , FJOURNAL =. 2016 , NUMBER =. doi:10.1214/15-AOS1378 , URL =
-
[36]
Ding, Yi and Zheng, Xinghua , TITLE =. Ann. Statist. , FJOURNAL =. 2024 , NUMBER =. doi:10.1214/24-aos2381 , URL =
-
[37]
39th Annual Meeting IMS, Atlanta, GA, 1975 , year=
Estimation of a covariance matrix , author=. 39th Annual Meeting IMS, Atlanta, GA, 1975 , year=
1975
-
[38]
Journal of Soviet Mathematics , volume=
Lectures on the theory of estimation of many parameters , author=. Journal of Soviet Mathematics , volume=. 1986 , publisher=
1986
-
[39]
Ledoit, Olivier and Wolf, Michael , TITLE =. Ann. Statist. , FJOURNAL =. 2020 , NUMBER =. doi:10.1214/19-AOS1921 , URL =
-
[40]
Journal of Financial Econometrics , volume=
The power of (non-) linear shrinking: A review and guide to covariance matrix estimation , author=. Journal of Financial Econometrics , volume=. 2022 , publisher=
2022
-
[41]
2024 , note=
Eigenvector distributions and optimal shrinkage estimators for large covariance and precision matrices , author=. 2024 , note=
2024
-
[42]
Silverstein, Jack W. and Choi, Sang-Il , TITLE =. J. Multivariate Anal. , FJOURNAL =. 1995 , NUMBER =. doi:10.1006/jmva.1995.1058 , URL =
-
[43]
Dobriban, Edgar , TITLE =. Random Matrices Theory Appl. , FJOURNAL =. 2015 , NUMBER =. doi:10.1142/S2010326315500197 , URL =
-
[44]
Xia, Ningning and Zheng, Xinghua , TITLE =. Ann. Statist. , FJOURNAL =. 2018 , NUMBER =. doi:10.1214/17-AOS1558 , URL =
-
[45]
Rio, Emmanuel , TITLE =. Electron. Commun. Probab. , FJOURNAL =. 2017 , PAGES =. doi:10.1214/17-ECP57 , URL =
-
[46]
Edwards, D. A. , TITLE =. Expo. Math. , FJOURNAL =. 2011 , NUMBER =. doi:10.1016/j.exmath.2011.06.005 , URL =
-
[47]
Computational Statistics & Data Analysis , volume=
Numerical implementation of the QuEST function , author=. Computational Statistics & Data Analysis , volume=. 2017 , publisher=
2017
-
[48]
Journal of the Royal Statistical Society Series B: Statistical Methodology , volume=
Maximum likelihood estimation for linear Gaussian covariance models , author=. Journal of the Royal Statistical Society Series B: Statistical Methodology , volume=. 2017 , publisher=
2017
-
[49]
2005 , PAGES =
Belinschi, Serban Teodor , TITLE =. 2005 , PAGES =
2005
-
[50]
Journal d'Analyse Math
A new approach to subordination results in free probability , author=. Journal d'Analyse Math. 2007 , publisher=
2007
-
[51]
2002 , PAGES =
Hatcher, Allen , TITLE =. 2002 , PAGES =
2002
-
[52]
Kosorok, Michael R. , TITLE =. 2008 , PAGES =. doi:10.1007/978-0-387-74978-5 , URL =
-
[53]
van der Vaart, Aad W. and Wellner, Jon A. , TITLE =. 1996 , PAGES =. doi:10.1007/978-1-4757-2545-2 , URL =
-
[54]
Yang, Fan , TITLE =. Electron. J. Probab. , FJOURNAL =. 2019 , PAGES =. doi:10.1214/19-ejp381 , URL =
-
[55]
von Sydow, Bj\"orn , TITLE =. Numer. Math. , FJOURNAL =. 1977/78 , NUMBER =. doi:10.1007/BF01389313 , URL =
-
[56]
Ledoit, Olivier and Wolf, Michael , TITLE =. Comput. Statist. Data Anal. , FJOURNAL =. 2017 , PAGES =. doi:10.1016/j.csda.2017.06.004 , URL =
-
[57]
2010 , publisher=
Spectral analysis of large dimensional random matrices , author=. 2010 , publisher=
2010
-
[58]
Mathematische Zeitschrift , volume=
Processes with free increments , author=. Mathematische Zeitschrift , volume=. 1998 , publisher=
1998
-
[59]
Ding, Xiucai and Yang, Fan , TITLE =. Ann. Statist. , FJOURNAL =. 2021 , NUMBER =. doi:10.1214/20-aos1995 , URL =
-
[60]
http://yann.lecun.com/exdb/mnist/ , year=
The MNIST database of handwritten digits , author=. http://yann.lecun.com/exdb/mnist/ , year=
-
[61]
Gin\'e, Evarist and Nickl, Richard , TITLE =. 2016 , PAGES =. doi:10.1017/CBO9781107337862 , URL =
-
[62]
arXiv preprint arXiv:2406.05811 , year=
CLT for Generalized Linear Spectral Statistics of High-dimensional Sample Covariance Matrices and Applications , author=. arXiv preprint arXiv:2406.05811 , year=
-
[63]
Ledoit, Olivier and P\'ech\'e, Sandrine , TITLE =. Probab. Theory Related Fields , FJOURNAL =. 2011 , NUMBER =. doi:10.1007/s00440-010-0298-3 , URL =
-
[64]
Rao, N. Raj and Mingo, James A. and Speicher, Roland and Edelman, Alan , TITLE =. Ann. Statist. , FJOURNAL =. 2008 , NUMBER =. doi:10.1214/07-AOS583 , URL =
-
[65]
Tony and Liang, Tengyuan and Zhou, Harrison H
Cai, T. Tony and Liang, Tengyuan and Zhou, Harrison H. , TITLE =. J. Multivariate Anal. , FJOURNAL =. 2015 , PAGES =. doi:10.1016/j.jmva.2015.02.003 , URL =
-
[66]
Li, Zeng and Lam, Clifford and Yao, Jianfeng and Yao, Qiwei , TITLE =. Ann. Statist. , FJOURNAL =. 2019 , NUMBER =. doi:10.1214/18-AOS1782 , URL =
-
[67]
Li, Jun and Chen, Song Xi , TITLE =. Ann. Statist. , FJOURNAL =. 2012 , NUMBER =. doi:10.1214/12-AOS993 , URL =
-
[68]
Jiang, Tiefeng and Yang, Fan , TITLE =. Ann. Statist. , FJOURNAL =. 2013 , NUMBER =. doi:10.1214/13-AOS1134 , URL =
-
[69]
Liu, Zhijun and Hu, Jiang and Bai, Zhidong and Song, Haiyan , TITLE =. Ann. Statist. , FJOURNAL =. 2023 , NUMBER =. doi:10.1214/23-aos2333 , URL =
-
[70]
2012 , publisher=
Introduction to non-commutative probability , author=. 2012 , publisher=
2012
-
[71]
and Guionnet, Alice and Zeitouni, Ofer , TITLE =
Anderson, Greg W. and Guionnet, Alice and Zeitouni, Ofer , TITLE =. 2010 , PAGES =
2010
-
[72]
and Zeitouni, Ofer , TITLE =
Anderson, Greg W. and Zeitouni, Ofer , TITLE =. Ann. Statist. , FJOURNAL =. 2008 , NUMBER =
2008
-
[73]
1999 , PAGES =
B\"ottcher, Albrecht and Silbermann, Bernd , TITLE =. 1999 , PAGES =
1999
-
[74]
, TITLE =
Brillinger, David R. , TITLE =. 1981 , PAGES =
1981
-
[75]
, TITLE =
Brillinger, David R. , TITLE =. 2001 , PAGES =
2001
-
[76]
Hannan, E. J. , TITLE =. 1970 , PAGES =
1970
-
[77]
2005 , PAGES =
L\"utkepohl, Helmut , TITLE =. 2005 , PAGES =
2005
-
[78]
1991 , PAGES =
L\"utkepohl, Helmut , TITLE =. 1991 , PAGES =
1991
-
[79]
2019 , publisher=
Multivariate time series analysis and applications , author=. 2019 , publisher=
2019
-
[80]
and Davis, Richard A
Brockwell, Peter J. and Davis, Richard A. , TITLE =. 2006 , PAGES =
2006
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