Seminar series
          
      Date
              Tue, 20 Oct 2020
      
      
          Time
        12:45 - 
        13:30
          Speaker
              Zhen Shao
          Organisation
              Oxford University
          We propose a subspace Gauss-Newton method for nonlinear least squares problems that builds a sketch of the Jacobian on each iteration. We provide global rates of convergence for regularization and trust-region variants, both in expectation and as a tail bound, for diverse choices of the sketching matrix that are suitable for dense and sparse problems. We also have encouraging computational results on machine learning problems.