title: Efficient Calculation of Polynomial Features on Sparse Matrices
abstract: We provide an algorithm for polynomial feature expansion that both operates on
  and produces a compressed sparse row matrix without any densification. For a
  vector of dimension D, density d, and degree k the algorithm has time complexity
  O(d^k * D^k) where k is the polynomial-feature order; this is an improvement by a factor d^k
  over the standard method.
authors: Andrew Nystrom John Hughes
hIndex: Andrew Nystrom 2