Abstract
A new wavelet-based estimation methodology, in the context of spatial functional regression, is proposed to discriminate between small-scale and large scale variability of spatially correlated functional data, defined by depth-dependent curves. Specifically, the discrete wavelet transform of the data is computed in space and depth to reduce dimensionality. Moment-based regression estimation is applied for the approximation of the scaling coefficients of the functional response. While its wavelet coefficients are estimated in a Bayesian regression framework. Both regression approaches are implemented from the empirical versions of the scaling and wavelet auto-covariance and cross-covariance operators, characterizing the correlation structure of the spatial functional response. Weather stations in ocean islands display high spatial concentration. The proposed estimation methodology overcomes the difficulties arising in the estimation of ocean temperature field at different depths, from long records of ocean temperature measurements in these stations. Data are collected from The World-Wide Ocean Optics Database. The performance of the presented approach is tested in terms of 10-fold cross-validation, and residual spatial and depth correlation analysis. Additionally, an application to soil sciences, for prediction of electrical conductivity profiles is also considered to compare this approach with previous related ones, in the statistical analysis of spatially correlated curves in depth.
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References
Almeida A (2005) Wavelet bases in generalized Besov spaces. J Math Anal Appl 304:198–211
Angelini C, De Canditiis D, Leblanc F (2003) Wavelet regression estimation in nonparametric mixed effect models. J Multivar Anal 85:267–291
Baladandayuthapani V, Mallick B, Hong M, Lupton J, Turner N, Caroll R (2008) Bayesian hierarchical spatially correlated functional data analysis with application to colon carcinoginesis. Biometrics 64:64–73
Basse, M., Diop, A., Dabo-Niang, S. (2008). Mean square properties of a class of kernel density estimates for spatial functional random variables. Annales De L’I.S.U.P. Publications de l’Institut de Statistique de l’Université de Paris
Bosq D (2000) Linear processes in function spaces. Springer-Verlag, New York
Bosq D, Ruiz-Medina MD (2014) Bayesian estimation in a high dimensional parameter framework. Electron J Stat 8:1604–1640
Cohen A, Daubechies I, Vial P (1994) Wavelets on the interval and fast wavelet transforms. J Appl Comput Harmon Anal 1:54–81
Daubechies I (1992) Ten lectures on wavelets SIAM. The Society for Industrial and Applied Mathematics, Philadelphia
Donoho DL (1993) Unconditional bases are optimal bases for data compression and for statistical estimation. J Appl Comput Harmon Anal 1:100–115
Finley AO, Banerjee S, Gelfand AE (2012) Bayesian dynamic modeling for large space-time datasets using Gaussian predictive processes. J Geogr Syst 14:29–47
Ganggang, Xu, Faming, L. and Genton, M. (2013). A bayesian spatio-temporal geostatistical model with an auxiliary lattice for large datasets. Stat Sin. Preprint doi:10.5705/ss.2013.085w
Gaposhkin VF (1974) The haar system as an unconditional basis in \(L_{p}[0, 1]\). Math Notes Acad Sci USSR 15:108–111
Giraldo R, Delicado P, Mateu J (2010) Continuous time-varying kriging for spatial prediction of functional data: an environmental application. J Agric Biol Environ Stat 15:66–82
Giraldo R, Delicado P, Mateu J (2012) Hierarchical clustering of spatially correlated functional data. Stat Neerlandica 66:403–421
Guillas S, Lai MJ (2010) Bivariate splines for spatial functional regression models. J R Stat Soc Ser B 22:477–497
Katzfuss M, Cressie N (2012) Bayesian hierarchical spatio-temporal smoothing for very large datasets. Environmetrics 23:94–107
Kelbert M, Leonenko NN, Ruiz-Medina MD (2005) Fractional random fields associated with stochastic fractional heat equations. Adv Appl Probab 108:108–133
Lehmann EL, Casella G (1998) Theory of point estimation. Springer-Verlag, New York
Leonenko NN, Ruiz-Medina MD (2006) Scaling laws for the multidimensional Burgers equation with quadratic external potencial. J Stat Phys 124:191–205
Monestiez P, Nerini D (2008) A cokriging method for spatial functional data with applications in oceanology. Functional and operational statistics. Contrib Stat 36:237–242
Nerini D, Monestiez P, Manté C (2010) Cokriging for spatial functional data. J Multivar Anal 101:409–418
Ruiz Medina MD, Espejo R, Romano E (2014) Spatial functional normal mixed effect approach for curve classification. Adv Data Anal Classif 8:257–285
Ruiz-Medina MD (2011) Spatial autoregressive and moving average Hilbertian processes. J Multivar Anal 102:292–305
Ruiz-Medina MD, Espejo RM (2012) Spatial autoregressive functional plug-in prediction of ocean surface temperature. Stoch Environ Res Risk Assess 26:335–344
Ruiz-Medina MD, Espejo R (2013) Integration of spatial functional interaction in the extrapolation of ocean surface temperature anomalies due to global warming. Int J Appl Earth Obs Geoinf 22:27–39
Ruiz-Medina MD, Fernndez-Pascual R (2010) Spatiotemporal filtering from fractal spatial functional data sequence. Stoch Environ Res Risk Assess 24:527–538
Sandwell DT (1987) Biharmonic spline interpolation of GEOS-3 and SEASAT altimeter data. Geophys Res Lett 14:139–142
Yang WH, Wikle CK, Holan SH, Sudduth K, Meyers DB (2015) Bayesian analysis of spatially-dependent functional responses with spatially-dependent multi-dimensional functional predictors. Stat Sin 25:205–223
Acknowledgments
This work has been supported in part by project MTM2012-32674 (co-funded with FEDER) of the DGI, MEC, Spain. We would like to thank Professors Yang, Wikley, Holanz, Myersx, and Sudduth for sending and allowing us to use their dataset to illustrate the estimation methodology proposed in this paper, which has been inspired and motivated by their proposal.
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Appendix
Appendix
In this appendix, for the ocean temperature, and the two covariates studied, salinity and relative fluorescence, we show the sample auto-correlation and cross-correlation functions, over the ten years analyzed, at nodes 1, 6 and 16, for certain depth intervals (see Figs. 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70 below), for the first region analyzed with longitude–latitude interval \([-85, -45] x [-30, -60],\) as well as for the second region with longitude–latitude interval \([-60, -52]\times [-35, -55]).\) In both regions, it can be appreciated the absence of downward sloping, or gradually decay for increasing lags, that supports the stationarity assumption in time for the above three magnitudes.
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Fernández-Pascual, R.M., Espejo, R. & Ruiz-Medina, M.D. Moment and Bayesian wavelet regression from spatially correlated functional data. Stoch Environ Res Risk Assess 30, 523–557 (2016). https://doi.org/10.1007/s00477-015-1130-5
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DOI: https://doi.org/10.1007/s00477-015-1130-5