abstract interpretation for neural networks
**Abstract Interpretation** for neural networks is the **application of formal verification techniques from program analysis to prove properties of neural networks** — over-approximating the set of possible outputs for a given set of inputs using abstract domains (intervals, zonotopes, polyhedra).
**Abstract Domains for NNs**
- **Intervals (Boxes)**: Simplest domain — equivalent to IBP. Fast but loose bounds.
- **Zonotopes**: Affine-form abstract domain that tracks linear correlations between variables — tighter than boxes.
- **DeepPoly**: Combines zonotopes with back-substitution for tighter approximation.
- **Polyhedra**: Most precise but computationally expensive — used for small networks.
**Why It Matters**
- **Sound**: Abstract interpretation provides sound over-approximations — if the verification passes, the property truly holds.
- **Scalable**: Zonotope and DeepPoly domains balance precision with scalability for medium-sized networks.
- **Properties**: Can verify robustness, monotonicity, fairness, and other safety properties.
**Abstract Interpretation** is **formal math for neural network properties** — using abstract domains to prove that neural networks satisfy desired safety properties.