arXiv subjects

Pascal Barbedor

Publications and source records attributed to Pascal Barbedor.

2 recordsLinked to original sources

arXiv2006

Independent Component Analysis and estimation of a quadratic functional

Independent component analysis (ICA) is linked up with the problem of estimating a non linear functional of a density, for which optimal estimators are well known. The precision of ICA is analyzed from the viewpoint of functional spaces in the wavelet framework. In particular, it is shown that, under Besov smoothness conditions, parametric rate of convergence is achieved by a U-statistic estimator of the wavelet ICA contrast, while the previously introduced plug-in estimator $\hat C^2\_j$, with moderate computational cost, has a rate in $n^{-4s\over 4s+d}$.

math.ST↗

arXiv2005

Independent Component Analysis by Wavelets

We propose an ICA contrast based on the density estimation of the observed signal and its marginals by means of wavelets. The risk of the associated moment estimator is linked with approximation properties in Besov spaces. It is shown to converge faster than the at least expected minimax rate carried over from the underlying density estimations. Numerical simulations performed on some common types of densities yield very competitive results, with a high sensitivity to small departures from independence.

math.ST↗