2670	 Efficient Implementation of a Variable Projection Algorithm for Nonlinear Least Squares Problems	 Nonlinear least squares frequently arise for which the variables to be solved for can be separated into a linear and a nonlinear part. A variable projection algorithm has been developed recently which is designed to take advantage of the structure of a problem whose variables separate in this way. This paper gives a slightly more efficient and slightly more general version of this algorithm than has appeared earlier. nonlinear least squares parameter estimation variable projection
