Train or sample a neural state-space model in trajectory space rather than drawing complete rollouts independently. Construct a space-time path graph whose vertices are latent states and local transition events, then update connected clusters of the entire trajectory using conditional Gibbs or Swendsen-Wang-like moves while preserving fixed initial, terminal, or event-count constraints. This should replace exponentially small forward-rollout success probabilities with local conditional updates…
Add an exact backward-conditioning module to a neural state-space model so trajectories satisfy a terminal label, target set, initial-state restriction, or prescribed event count without rejection. The module computes a backward feasibility message and reweights each neural transition toward states that can still satisfy the constraint, producing a conditioned process equivalent to a Doob transform. For large latent spaces, the exact message can be approximated by a value network and its…
Represent a stochastic recurrent or state-space model as an event trajectory and train it with trajectories conditioned on a rare terminal event, such as a catastrophic state, a constraint violation, or an unusually large prediction error. Instead of simulating forward until the event occurs, update connected spacetime clusters while holding the initial state and terminal event boundary fixed, so every retained trajectory is useful for rare-event learning. This provides a principled alternative…