Neural Network Methods

This page records how the neural methods are validated. The neural_solver package (JAX) implements mesh-free deep BSDE, deep HJB (DGM), and neural operator methods. Unlike the classical solver, its validation is not part of cargo test: it is exercised by the Python test suite in neural_solver/tests/ and its measured results are documented in the neural empirical results. This page is the single-place summary; the per-architecture numbers are stated once in the empirical pages and are not duplicated here beyond the headline figures.

The neural methods are validated in two ways:

  • Against exact references - the same closed forms the classical solver uses (Black-Scholes, Merton, LQ, jump-LQ), and for the jump path a Riccati closed form that exercises the learned jump integrand directly.
  • Against the classical solver's committed values - reference agreement with no training: the JAX closed forms reproduce the Rust solver values to float32 precision.
ProblemNeural methodReferenceObtained errorSource
Black-Scholes calldeep BSDEclosed form0.19%-2.29% (per seed)results
Black-Scholes callDGMclosed form1.10%results
Merton portfoliodeep BSDEclosed formwithin 10% (test tolerance)results
jump-LQdeep BSDERiccati closed form0.70%results
jump-LQDGMRiccati closed form1.33%results
Merton jumpdeep BSDEclosed form0.022%results
Reference agreementJAX closed formsRust solver values1e-6 (float32)results

Cross-architecture cost and error (deep BSDE vs DGM vs operator, including the no-exact-solution targets) are in comparison; which architecture fits which exact-solution problem is in coverage. The reference schema the agreement check consumes is documented in usage.