Soft-LOST: EM on a Mixture of Oriented Lines

  • Paul D. O’Grady
  • Barak A. Pearlmutter
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3195)


Robust clustering of data into overlapping linear subspaces is a common problem. Here we consider one-dimensional subspaces that cross the origin. This problem arises in blind source separation, where the subspaces correspond directly to columns of a mixing matrix. We present an algorithm that identifies these subspaces using an EM procedure, where the E-step calculates posterior probabilities assigning data points to lines and M-step repositions the lines to match the points assigned to them. This method, combined with a transformation into a sparse domain and an L 1-norm optimisation, constitutes a blind source separation algorithm for the under-determined case.


Speech Signal Independent Component Analysis Blind Source Separation Line Separation Line Orientation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Paul D. O’Grady
    • 1
  • Barak A. Pearlmutter
    • 1
  1. 1.Hamilton InstituteNational University of IrelandMaynooth, Co. KildareIreland

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