Case-Based Argumentation via Process Models

We introduce AHEAD (Analogical Hypothesis Elaborator for Activity Detection), a software system we are developing for the DARPA EELD (Evidence Extraction and Link Discovery) program. AHEAD performs case-based hypothesis elaboration using process models. We are applying AHEAD, which embodies a domain-independent approach, to elaborate hypothesized hostile activities. In this application, AHEAD is given as input (1) structured evidence and (2) a hypothesis concerning the activities of an asymmetric adversary (e.g., a terrorist organization). The system outputs a detailed symbolic argument supporting and/or opposing the given hypothesis. Combining case- based/analogical reasoning techniques, using the FIRE Analogy Server with qualitative functional processes represented as Task-Method-Knowledge models, AHEAD extracts additional implications of the hypothesis to develop a coherent argument that supports and/or contradicts it. We detail AHEAD’s design, its role in EELD, its implementation status, and our plans for its evaluation.