Search Results - "Olhede, S. C."

Extracting waves and vortices from Lagrangian trajectories by Lilly, J. M., Scott, R. K., Olhede, S. C.

“…A method for extracting time‐varying oscillatory motions from time series records is applied to Lagrangian trajectories from a numerical model of eddies…”
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The growing ubiquity of algorithms in society: implications, impacts and innovations by Olhede, S. C., Wolfe, P. J.

“…The growing ubiquity of algorithms in society raises a number of fundamental questions concerning governance of data, transparency of algorithms, legal and…”
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Local linear graphon estimation using covariates by Chandna, S, Olhede, S C, Wolfe, P J

“…Summary We consider local linear estimation of the graphon function, which determines probabilities of pairwise edges between nodes in an unlabelled network…”
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Detecting multivariate interactions in spatial point patterns with Gibbs models and variable selection by Rajala, T., Murrell, D. J., Olhede, S. C.

“…We propose a method for detecting significant interactions in very large multivariate spatial point patterns. This methodology thus develops high dimensional…”
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Testing for Equivalence of Network Distribution Using Subgraph Counts by Maugis, P.-A. G., Olhede, S. C., Priebe, C. E., Wolfe, P. J.

“…We consider that a network is an observation, and a collection of observed networks forms a sample. In this setting, we provide methods to test whether all…”
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Modulated oscillations in many dimensions by Olhede, S. C.

“…Modulated oscillations are described via their time-varying amplitude and frequency. For multivariate signals, there is structure in the signal beyond this…”
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Local directional denoising by Olhede, S.C., Walden, A.T.

“…Denoising of complex-valued signals involves the relationships between the real and imaginary parts of the signal. The authors introduce the idea of local…”
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Generalized Morse wavelets by Olhede, S.C., Walden, A.T.

“…This paper examines the class of generalized Morse wavelets, which are eigenfunction wavelets suitable for use in time-varying spectrum estimation via…”
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On probability density functions for complex variables by Olhede, S.C.

“…Complex random variables arise naturally in many settings and their properties are of general interest. Past work on complex variables has mainly focused on…”
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The growing ubiquity of algorithms in society: implications, impacts and innovations by Olhede, S. C., Wolfe, P. J.

“…The growing ubiquity of algorithms in society raises a number of fundamental questions concerning governance of data, transparency of algorithms, legal and…”
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On the Analytic Wavelet Transform by Lilly, Jonathan M, Olhede, Sofia C

“…An exact and general expression for the analytic wavelet transform of a real-valued signal is constructed, resolving the time-dependent effects of…”
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Higher-Order Properties of Analytic Wavelets by Lilly, J.M., Olhede, S.C.

“…The influence of higher-order wavelet properties on the analytic wavelet transform behavior is investigated, and wavelet functions offering advantageous…”
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‘Analytic’ wavelet thresholding by Olhede, Sofia C., Walden, Andrew T.

“…We introduce so-called analytic stationary wavelet transform thresholding where, using the discrete Hilbert transform, we create a complex-valued ‘analytic’…”
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Modulated oscillations in many dimensions by Olhede, S. C.

“…Modulated oscillations are described via their timevarying amplitude and frequency. For multivariate signals, there is structure in the signal beyond this…”
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Statistical inference for network samples using subgraph counts by Maugis, P-A. G, Priebe, Carey E, Olhede, S. C, Wolfe, P. J

“…We consider that a network is an observation, and a collection of observed networks forms a sample. In this setting, we provide methods to test whether all…”
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Generalized Morse Wavelets as a Superfamily of Analytic Wavelets by Lilly, J. M., Olhede, S. C.

“…The generalized Morse wavelets are shown to constitute a superfamily that essentially encompasses all other commonly used analytic wavelets, subsuming eight…”
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Noise reduction in directional signals using multiple Morse wavelets illustrated on quadrature Doppler ultrasound by Olhede, S.C., Walden, A.T.

“…The use of multiple complex-valued Morse wavelets for the scalogram study of signals which are unidirectional at any time, but are bidirectional overall is…”
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Fractional Brownian motion, the Matern process, and stochastic modeling of turbulent dispersion by Lilly, J. M, Sykulski, A. M, Early, J. J, Olhede, S. C

“…Nonlinear Processes in Geophysics, 24: 481-514 (2017) Stochastic process exhibiting power-law slopes in the frequency domain are frequently well modeled by…”
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Large‐sample properties of the periodogram estimator of seasonally persistent processes by Olhede, Sofia C., McCoy, Emma J., Stephens, David A.

“…Seasonally persistent models were first introduced by Anděl (1986) and Gray et al. (1989) to extend autoregressive moving‐average and fractionally differenced…”
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Fractional Brownian motion, the Matérn process, and stochastic modeling of turbulent dispersion by Lilly, Jonathan M, Sykulski, Adam M, Early, Jeffrey J, Olhede, Sofia C

“…Stochastic processes exhibiting power-law slopes in the frequency domain are frequently well modeled by fractional Brownian motion (fBm), with the spectral…”
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