Approximate Gauss-Newton Methods for Nonlinear Least Squares Problems. - Serge Gratton; Amos S. Lawless; Nancy K. Nichols (SIAM J. Optim., 2007)

The conditioning of least-squares problems in variational data assimilation. - Jemima M. Tabeart; Sarah L. Dance; Stephen A. Haben; Amos S. Lawless; Nancy K. Nichols; Joanne A. Waller (Numer. Linear Algebra Appl., 2018)

The conditioning of least squares problems in preconditioned variational data assimilation. - Jemima M. Tabeart; Sarah L. Dance; Amos S. Lawless; Nancy K. Nichols; Joanne A. Waller (CoRR, 2020)

Spectral estimates for saddle point matrices arising in weak constraint four-dimensional variational data assimilation. - Ieva Dauzickaite; Amos S. Lawless; Jennifer A. Scott; Peter Jan van Leeuwen (Numer. Linear Algebra Appl., 2020)

Randomised preconditioning for the forcing formulation of weak constraint 4D-Var. - Ieva Dauzickaite; Amos S. Lawless; Jennifer A. Scott; Peter Jan van Leeuwen (CoRR, 2021)

On preconditioning the state formulation of incremental weak constraint 4D-Var. - Ieva Dauzickaite; Amos S. Lawless; Jennifer A. Scott; Peter Jan van Leeuwen (CoRR, 2021)

Nonlinear Conditional Model Bias Estimation for Data Assimilation. - Jason A. Otkin; Roland W. E. Potthast; Amos S. Lawless (SIAM J. Appl. Dyn. Syst., 2021)

New bounds on the condition number of the Hessian of the preconditioned variational data assimilation problem. - Jemima M. Tabeart; Sarah L. Dance; Amos S. Lawless; Nancy K. Nichols; Joanne A. Waller (Numer. Linear Algebra Appl., 2022)

Conditioning of hybrid variational data assimilation. - Shaerdan Shataer; Amos S. Lawless; Nancy K. Nichols (Numer. Linear Algebra Appl., 2024)

An Introduction to Solving the Least-Squares Problem in Variational Data Assimilation. - Ieva Dauzickaite; M. A. Freitag; Selime Gürol; Amos S. Lawless; A. Ramage; Jennifer A. Scott; Jemima M. Tabeart (CoRR, 2025)