User interfaces with semi-formal representations

When designing mixed-initiative systems, full formalization of all potentially relevant knowledge may not be cost-effective or practical. This paper motivates the need for semi-formal representations that combine machine-processable structures with free text statements, and discusses the need to design them in a way that makes the free text more amenable to automated structuring and processing. Our work is done in the context of argumentation systems, and has explored a range of tradeoffs in combining informal free-text statements with formal connectors. The paper compares alternative argument representations which combine structured argument connectors with free text. We discuss merits of the systems based on a variety of analysis structures that we have collected from Web users to date.