A Framework for Incremental Query Formulation in Mixed-Initiative Case-Based Reasoning

Query formulation is a primary task in the retrieval phase of the case-based reasoning (CBR) cycle, and incremental variants of this task are a distinguishing characteristic of some mixed-initiative CBR approaches (e.g., those that implement a conversational CBR methodology). However, it has rarely been the focus of analysis, which complicates comparing these approaches. We identify the primitive decisions that a CBR system or its user can make during a constrained form of incremental query formulation, and discuss how initiative can be shared when sequencing these decisions. We use this framework to compare some existing mixed-initiative CBR approaches that incrementally formulate queries.