Plenary Talk
Reasoning with Diagrams: Observation, Inference and Overspecificity
Gem Stapleton
University of Brighton
Brighton, United Kingdom
Abstract:
The ability of diagrams to convey information effectively comes, in part, from their ability to make facts explicit that would otherwise need to be inferred. This type of advantage has often been referred to as a free ride and was deemed to occur only when a diagram was obtained by translating a symbolic representation of information. Recent work generalised free rides, introducing the idea of an observational advantage, where the existence of such a translation is not required. In this talk, I will provide an overview of the theory of observation. Using observability, a formal characterisation of observational advantages can be explored. The talk will proceed to demonstrate the theory of observation and observational advantages by applying the concepts to set theory and Euler diagrams without existential import. It has been shown that Euler diagrams without existential import have significant observational advantages over set theory: they are observationally complete. The talk will then explore to what extent Euler diagrams with existential import are observationally complete with respect to set-theoretic sentences. In particular, it will be shown that existential import significantly limits the cases when observational completeness arises, due to the potential for overspecificity. These two results formally support Larkin and Simon's claim that “a diagram is (sometimes) worth ten thousand words”.
(Note: This is joint research with Atsushi Shimojima and Mateja Jamnik)
About the Speaker:
Dr Gem Stapleton is a Reader in Computer Science at the University of Brighton. She has over 120 publications and received five Best Paper Awards at international conferences. A major focus of her research has been on developing diagrammatic logics that support accessible reasoning. As part of this effort, she has devised layout algorithms for diagrams that incorporate geometric and topological constraints which are important for usability. As well as having a strong mathematical element, her research also encompasses empirical HCI to ensure the usability of her theoretical work. She has been PI and Co-I on major grants from the UK’s EPSRC and the Leverhulme Trust. Gem has also organised many international conferences, was Chair of the Diagrams Steering Committee (until 2016) and is a member of the VL/HCC Steering Committee.