RT journal article T1 The dual wavelet spectra: an alternative perspective on Hurst exponent estimation with application to mammogram classification A1 J. Hinton, Raymond A1 Vidakovic, Brani A1 Ramírez Cobo, Josefa A2 Estadística e Investigación Operativa K1 Scaling K1 non-decimated wavelet transform K1 2D fractional Brownian motion K1 image classification AB The wavelet spectra is a common starting point for estimating the Hurst exponentof a self-similar signal using wavelet-based techniques. The decay of the log2 averageenergyofthedetailwaveletcoefficientsasafunctionofthelevelofsignaldecompositioncan be used to construct estimators for this parameter. In this paper, we expandon previous work which introduced the “dual” wavelet spectra, where decompositionlevels are instead treated as a function of energy values, and propose a relationshipbetween its slope and the Hurst exponent, creating a new estimator. We focus onthe 2D case, making the method suitable for analyzing complex image data. Theeffectiveness of this estimator and its sensitivity to several settings are demonstratedthrough a simulation study. Finally, we show how the technique performs as a featureextraction method by applying it to the task of detecting the presence of breast cancerin mammogram images. Dual spectra wavelet features had a statistically significanteffect on the log-odds of Cancer. YR 2026 FD 2026-02 LK http://hdl.handle.net/10498/38829 UL http://hdl.handle.net/10498/38829 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 07-nov-2026