Nik Swoboda

Using DAG transformations to verify Euler/Venn homogeneous and Euler/Venn FOL heterogeneous rules of inference

In this paper we will present a graph-transformation based method for the verification of heterogeneous first order logic (FOL) and Euler/Venn proofs. In previous work, it has been shown that a special collection of directed acyclic graphs (DAGs) can be used interchangeably with Euler/Venn diagrams in reasoning processes. Thus, proofs which include Euler/Venn diagrams can be thought of as proofs with DAGs where steps involving only Euler/Venn diagrams can be treated as particular DAG transformations. Here we will show how the characterization of these manipulations can be used to verify Euler/Venn proofs. Also, a method for verifying the use of heterogeneous Euler/Venn and FOL reasoning rules will be presented that is also based upon DAG transformations .

Graphical Language Games: Interactional Constraints on Representational Form

The emergence of shared symbol systems is considered to be a pivotal moment in human evolution and human development. These changes are normally explained by reference to changes in peoples internal cognitive processes. We present 2 experiments which provide evidence that changes in the external, collaborative processes that people use to communicate can also affect the structure and organization of symbol systems independently of cognitive change. We propose that mutual-modifiability-opportunities for people to edit or manipulate each others contributions-is a key constraint on the emergence of complex symbol systems. We discuss the implications for models of language development and the origins of compositionality.

Graphical representation in graphical dialogue

Abstract This paper explores the influence of communicative interaction on the form of graphical representations. A referential communication task is described which involves exclusively graphical dialogue. In this task subjects communicate about pieces of music by drawing. The drawings produced fall into two basic types: Abstract and Figurative. Three hypotheses are developed about the factors influencing the use of these drawing types: efficiency of production, suitability for the task and level of communicative interaction. Experimental evidence is presented which indicates that the drawing types do not differ in the amount of effort required to produce them. The results indicate that (1) Abstract drawings are more effective than Figurative drawings for comparative tasks and (2) a key constraint on their use is level of direct communicative interaction. It is argued that these observations result from differences in the underlying semantic models of music associated with the drawing types and the consequences these differences have for communicative coordination.

Modeling Heterogeneous Systems

Reasoning practices and decision making often require information from many different sources, which can be both sentential and diagrammatic. In such situations, there are many advantages to reasoning with the diagrams themselves, as opposed to re-expressing the information content of the diagram in sentential form and reasoning in an abstract sentential language. Thus for these practices, being able to extract and re-express pieces of information from one kind of representation into another is essential. The main goal of this paper is to propose a general framework for the modeling of heterogeneous reasoning systems and, most importantly, heterogeneous rules of inference in those systems. Unlike some other work in designing heterogeneous systems, our purpose will not be to define just one notion of heterogeneous inference, but rather to provide a framework in which many different kinds of heterogeneous rules of inference can be defined. After proposing this framework, we will then show how it can be applied to a sample heterogeneous system to define a number of different heterogeneous rules of inference. We will also discuss how the framework can be used to define rules of inference similar to the Observe Rule in Barwise and Etchemendys Hyperproof system.

A Tool for Performing and Analysing Experiments on Graphical Communication

Drawing is a basic mode of human communication. This paper describes a tool, written in Java, that is designed to support the capture and analysis of interactive graphical communication for experimental purposes. It is based around a simple ‘virtual’ whiteboard that supports remote and co-present graphical interaction between pairs of subjects. Logs of the subjects’ drawing activity and the dynamics of the communicative exchange are captured for subsequent statistical analysis. The software supports experimental manipulation of graphical interaction by providing control over update and layout of the whiteboard area. It also supports manipulation of patterns of group interaction through the management of multiple simultaneous shared whiteboard connections. Lastly, a playback tool supports fine-grained analysis of collaborative drawing activity.

Openproof - A Flexible Framework for Heterogeneous Reasoning

In this paper we describe the Openproof heterogeneous reasoning framework. The Openproof framework provides support for the implementation of heterogeneous reasoning environments, i.e., environments for writing arguments or proofs involving a number of different kinds of representation. The resulting environments are in a similar spirit to our Hyperproofprogram, though the Openproof framework goes beyond Hyperproofby providing facilities for the inclusion of a variety of representation systems in the same environment. The framework serves as the core of a number of widely used educational programs including Fitch.

Learning to use the openbox: a framework for the implementation of heterogeneous reasoning

In this tutorial we will present the Openbox, a framework for constructing heterogeneous reasoning systems. Heterogeneous reasoning is reasoning involving multiple representations. A common example is using a map (diagram) together with an address (sentence) to plan a route from one point to another. This kind of reasoning may involve diagrams of multiple types, diagrams and sentences, and/or multiple instances of the same diagram type. Reasoning with sentences, or with a single diagram are special cases of the general heterogeneous setting.

Reasoning with coincidence grids-A sequent-based logic and an analysis of complexity

Information is often represented in tabular format in everyday documents such as balance sheets, sales figures, and so on. Tables represent an interesting point in the spectrum of representation systems between pictures and sentences, since some aspects of tables are sentential or conventional in nature, while others are graphical. In this paper we describe a sequent-based logic for a particular formalized tabular representation system, that of coincidence grids. After presenting this system we will then provide an analysis of the complexity of reasoning with this formalism showing that the problem of deciding whether a coincidence grid can be consistently completed is NP-Complete.

Co-ordinating Conventions in Graphical Dialogue: Effects of Repetition and Interaction

In recent studies of graphical dialogue, the level of communicative interaction has been identified as an important influence on the form of graphical representations. Here, we report the results of a ‘Pictionary-like’ concept drawing experiment which compares the contribution of repetition and level of interaction to changes in the form of graphical representations. In one version of the task, participants repeatedly produce drawings of the same set of items. In the other participants produce drawings of different items. In both cases, when the level of communicative interaction between the participants varies, the form of the representation produced by the pair also varies. These results suggest that three different processes are contributing to changes in graphical form in these tasks: practise, reduction and mutual-modification. We propose that the last of these, mutual-modifiability is important for the evolution of new conventions.

An introduction to AI course with guide robot programming assignments

In this paper we describe a collection of course materials designed to be used in an undergraduate introduction to artificial intelligence (AI) course. These materials include three programming assignments, each touching upon core AI topics, which require that the students build the main functionalities of a guide robot. These assignments were carefully designed to allow the same solution to work both with a robot simulator and an inexpensive web-cam as well as with real robots. An overview of the course and the assignments is given along with references to online versions of the resources developed to teach the course.