Detecting independence of random vectors: generalized distance covariance and Gaussian covariance
Volume 5, Issue 3 (2018), pp. 353–383
Pub. online: 19 September 2018
Type: Research Article
Open Access
Received
29 June 2018
29 June 2018
Revised
23 August 2018
23 August 2018
Accepted
30 August 2018
30 August 2018
Published
19 September 2018
19 September 2018
Abstract
Distance covariance is a quantity to measure the dependence of two random vectors. We show that the original concept introduced and developed by Székely, Rizzo and Bakirov can be embedded into a more general framework based on symmetric Lévy measures and the corresponding real-valued continuous negative definite functions. The Lévy measures replace the weight functions used in the original definition of distance covariance. All essential properties of distance covariance are preserved in this new framework.
From a practical point of view this allows less restrictive moment conditions on the underlying random variables and one can use other distance functions than Euclidean distance, e.g. Minkowski distance. Most importantly, it serves as the basic building block for distance multivariance, a quantity to measure and estimate dependence of multiple random vectors, which is introduced in a follow-up paper [Distance Multivariance: New dependence measures for random vectors (submitted). Revised version of arXiv: 1711.07775v1] to the present article.
References
Bakirov, N.K., Székely, G.J.: Brownian covariance and central limit theorem for stationary sequences. Theory of Probability and its Applications 55(3), 371–394 (2011) MR2768533. https://doi.org/10.1137/S0040585X97984954
Banyamini, Y., Lindenstrauss, J.: Geometric Nonlinear Functional Analysis. American Mathematical Society, Providence (RI) (2000) MR1727673
Berg, C., Forst, G.: Potential Theory on Locally Compact Abelian Groups. Springer, Berlin (1975) MR0481057
Berrett, T.B., Samworth, R.J.: Nonparametric independence testing via mutual information. arXiv: 1711.06642v1 (2017)
Berschneider, G., Böttcher, B.: On complex Gaussian random fields, Gaussian quadratic forms and sample distance multivariance. arXiv: 1808.07280v1 (2018)
Bickel, P.J., Xu, Y.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1266–1269 (2009) MR2752128. https://doi.org/10.1214/09-AOAS312A
Böttcher, B.: Dependence structures - estimation and visualization using distance multivariance. arXiv: 1712.06532v1 (2017)
Böttcher, B., Keller-Ressel, M., Schilling, R.L.: Distance Multivariance: New dependence measures for random vectors (submitted). Revised version of arXiv: 1711.07775v1 (2017)
Böttcher, B., Schilling, R.L., Wang, J.: Lévy-Type Processes: Construction, Approximation and Sample Path Properties. Lecture Notes in Mathematics, Lévy Matters, vol. 2099. Springer (2013) MR3156646. https://doi.org/10.1007/978-3-319-02684-8
Cope, L.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1279–1281 (2009). doi:https://doi.org/10.1214/00-AOAS312C MR2752130. https://doi.org/10.1214/00-AOAS312C
Csörgő, S.: Limit behaviour of the empirical characteristic function. The Annals of Probability, 130–144 (1981)MR0606802
Csörgő, S.: Multivariate empirical characteristic functions. Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete 55(2), 203–229 (1981). MR0608017. https://doi.org/10.1007/BF00535160
Csörgő, S.: Testing for independence by the empirical characteristic function. Journal of Multivariate Analysis 16(3), 290–299 (1985) MR0793494. https://doi.org/10.1016/0047-259X(85)90022-3
Feuerverger, A.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1282–1284 (2009) MR2752131. https://doi.org/10.1214/09-AOAS312D
Feuerverger, A., Mureika, R.A.: The empirical characteristic function and its applications. The Annals of Statistics, 88–97 (1977)MR0428584
Genovese, C.R.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1299–1302 (2009). doi:https://doi.org/10.1214/09-AOAS312G MR2752134. https://doi.org/10.1214/09-AOAS312G
Gretton, A., Fukumizu, K., Sriperumbudur, B.K.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1285–1294 (2009). MR2752132. https://doi.org/10.1214/09-AOAS312E
Jacob, N.: Pseudo-Differential Operators and Markov Processes I. Fourier Analysis and Semigroups. Imperial College Press, London (2001) MR1873235. https://doi.org/10.1142/9781860949746
Jacob, N., Knopova, V., Landwehr, S., Schilling, R.L.: A geometric interpretation of the transition density of a symmetric Lévy process. Science China: Mathematics 55, 1099–1126 (2012) MR2925579. https://doi.org/10.1007/s11425-012-4368-0
Jin, Z., Matteson, D.S.: Generalizing Distance Covariance to Measure and Test Multivariate Mutual Dependence. arXiv: 1709.02532v1 (2017)
Kosorok, M.R.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1270–1278 (2009). doi:https://doi.org/10.1214/09-AOAS312B MR2752129. https://doi.org/10.1214/09-AOAS312B
Lyons, R.: Distance covariance in metric spaces. The Annals of Probability 41(5), 3284–3305 (2013) MR3127883. https://doi.org/10.1214/12-AOP803
Newton, M.A.: Introducing the discussion paper by Székely and Rizzo. The Annals of Applied Statistics 3(4), 1233–1235 (2009). MR2752126. https://doi.org/10.1214/09-AOAS34INTRO
Rémillard, B.: Discussion of: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1295–1298 (2009). doi:https://doi.org/10.1214/09-AOAS312F MR2752133. https://doi.org/10.1214/09-AOAS312F
Sasvári, Z.: Positive Definite and Definitizable Functions. Akademie-Verlag, Berlin (1994) MR1270018
Sato, K.: Lévy Processes and Infinitely Divisible Distributions. Cambridge University Press, Cambridge (1999) MR1739520
Schilling, R., Schnurr, A.: The symbol associated with the solution of a stochastic differential equation. Electronic Journal of Probability 15, 1369–1393 (2010) MR2721050. https://doi.org/10.1214/EJP.v15-807
Schilling, R.L., Song, R., Vondraček, Z.: Bernstein Functions. Theory and Applications, 2nd edn. de Gruyter (2012) MR2978140. https://doi.org/10.1515/9783110269338
Schoenberg, I.J.: Metric spaces and positive definite functions. Transactions of the American Mathematical Society 44(3), 522–536 (1938) MR1501980. https://doi.org/10.2307/1989894
Serfling, R.J.: Approximation Theorems of Mathematical Statistics. John Wiley & Sons (2009) MR0595165
Székely, G.J., Rizzo, M.L.: Hierarchical clustering via joint between-within distances: Extending ward’s minimum variance method. Journal of Classification 22(2), 151–183 (2005) MR2231170. https://doi.org/10.1007/s00357-005-0012-9
Székely, G.J., Rizzo, M.L.: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1236–1265 (2009) MR2752127. https://doi.org/10.1214/09-AOAS312
Székely, G.J., Rizzo, M.L.: Rejoinder: Brownian distance covariance. The Annals of Applied Statistics 3(4), 1303–1308 (2009). doi:https://doi.org/10.1214/09-AOAS312REJ MR2752135. https://doi.org/10.1214/09-AOAS312REJ
Székely, G.J., Rizzo, M.L.: On the uniqueness of distance covariance. Statistics and Probability Letters 82(12), 2278–2282 (2012) MR2979766. https://doi.org/10.1016/j.spl.2012.08.007
Székely, G.J., Rizzo, M.L., Bakirov, N.K.: Measuring and testing dependence by correlation of distances. The Annals of Statistics 35(6), 2769–2794 (2007) MR2382665. https://doi.org/10.1214/009053607000000505
Ushakov, N.G.: Selected Topics in Characteristic Functions. VSP (1999) MR1745554. https://doi.org/10.1515/9783110935981
Witting, H., Müller-Funk, U.: Mathematische Statistik II. Teubner, Stuttgart (1995) MR1363716. https://doi.org/10.1007/978-3-322-90152-1
Zastavnyi, V.P.: On positive definiteness of some functions. Journal of Multivariate Analysis 73(3), 55–81 (2000) MR1766121. https://doi.org/10.1006/jmva.1999.1864