Portfolio optimization involves selecting asset weights to minimize a risk-reward objective, such as portfolio variance.
Sparse portfolio selection imposes a restriction where only a limited number of assets can be included from a larger pool.
Proposed scalable gradient-based approach transforms the sparse selection problem into a constrained continuous optimization task using Boolean relaxation.
The algorithm allows for stable convex starting points, controlled progression towards a sparse binary solution, and matches commercial solvers' results in most cases.