- Numerical methods for solving optimization problems and systems of nonlinear equations, in particular, Newton-type, stable secant and interpolation methods, globalization strategies.
- Cardinality-constrained optimization.
- Inverse problems, multilinear least-squares, nonsmooth optimization and equations.
- Linear and nonlinear saddle problems and monotone equations.
- Monotonic regression: data fitting and interpolation.
- TSP-related problems.
- Hop-restricted shortest path and Steiner tree problems in graphs.