Approximately 70 % of the source code of a software system consists of identifiers. Hence, the names chosen as identifiers are of paramount importance for the readability of computer programs and therewith their comprehensibility. However, virtually every programming language allows programmers to use almost arbitrary sequences of characters as identifiers which far too often results in more or less meaningless or even misleading naming. Coding style guides address this problem but are usually limited to general and hard to enforce rules like “identifiers should be self-describing”. This paper renders adequate identifier naming far more precisely. A formal model, based on bijective mappings between concepts and names, provides a solid foundation for the definition of precise rules for concise and consistent naming. The enforcement of these rules is supported by a tool that incrementally builds and maintains a complete identifier dictionary while the system is being developed. The identifier dictionary explains the language used in the software system, aids in consistent naming, and improves productivity of programmers by proposing suitable names depending on the current context.

In this paper, we introduce an integrated approach to the development of spatial hypertext. This approach brings together several theories and techniques concerning semantic structures, and streamlines the transformation from implicit semantic structures to a semantic space rendered in virtual reality. Browsing and querying become natural, inherent, and compatible activities within the same semantic space. The overall design principle is based on the theory of cognitive maps. Techniques such as latent semantic indexing, Pathfinder network scaling, and virtual reality modelling are used in harmony. The value of this integrated approach is discussed based on initial results of a recent empirical study, which suggests that the spatial metaphor is intuitive and particularly useful when dealing with implicit information structures, or when a highly flexible and extensible virtual environment is required. Search strategies in association with the spatial hypertext and further work are also discussed.

This paper describes a generic approach to the design of a 3D virtual environment for visual navigation. The basic design principle is that users need to understand how an environment is organised and how they can utilise the knowledge to find their way through the environment. In this paper, we focus on the relationship between implicit semantic structures associated with a collection of domain-specific documents and users' cognitive needs in the context of visual navigation. We extend the notion of Pathfinder networks in order to represent implicit semantic structures in a 3D virtual environment. Users' cognitive needs in visual navigation are conceptualised based on the concept of cognitive maps

This article presents a novel automatic method (AutoSummENG) for the evaluation of summarization systems, based on comparing the character n-gram graphs representation of the extracted summaries and a number of model summaries. The presented approach is language neutral, due to its statistical nature, and appears to hold a level of evaluation performance that matches and even exceeds other contemporary evaluation methods. Within this study, we measure the effectiveness of different representation methods, namely, word and character n-gram graph and histogram, different n-gram neighborhood indication methods as well as different comparison methods between the supplied representations. A theory for the a priori determination of the methods ’ parameters along with supporting experiments concludes the study to provide a complete alternative to existing methods concerning the automatic summary system evaluation process.

Real-time control skills are ordinarily tacit --- their possessors cannot explicitly communicate them. But given sufficient sampling of a trained expert's input--output behaviour, machine learning programs have been found capable of constructing rules which, when run as programs, deliver behaviours similar to those of the original exemplars. These `clones' are in effect symbolic representations of subcognitive behaviours. After validation on simple pole-balancing tasks, the principles have been successfully generalized in flight-simulator experiments, both by Sammut and others at UNSW, and by Camacho at the Turing Institute. A flight plan switches control through a sequence of logically concurrent sets of reactive behaviours. Each set can be thought of as a committee of subpilots who are respectively specialized for rudder, elevators, rollers, thrust, etc. The chairman (the flight plan) knows only the mission sequence, and how to recognize the onset of each stage. This treatment is ess...

We consider two issues in polynomial-time exact learning of concepts using membership and equivalence queries: (1) errors or omissions in answers to membership queries, and (2) learning finite variants of concepts drawn from a learnable class. To study

) Robert H. Sloan Dept. of Electrical Eng. and Computer Science University of Illinois at Chicago Chicago, IL 60607 sloan@eecs.uic.edu Gyorgy Turan x Dept. of Math., Stat., and Comp. Sci. University of Illinois at Chicago, Automata Theory Research Group Hungarian Academy of Sciences, Szeged U11557@uicvm.uic.edu Abstract We investigate learning with membership and equivalence queries assuming that the information provided to the learner is incomplete. By incomplete we mean that some of the membership queries may be answered by "I don't know." This model is a worst-case version of the incomplete membership query model of Angluin and Slonim. It attempts to model practical learning situations, including an experiment of Lang and Baum that we describe, where the teacher may be unable to answer reliably some queries that are critical for the learning algorithm. We present algorithms to learn monotone k-term DNF with membership queries only, and to learn monotone DNF with membership ...

The concept of a weakly intrusive ambient soundscape (WISP) is presented as a means to provide a peripheral awareness of processes beyond a user's immediate attention. The WISP is a component in a larger environment for ubiquitous computing, centered around a conference room scenario. The experiences from a demonstration prototype indicate that the choice of sounds and the intensity of their presentation can greatly influence the way the WISP is perceived. The work relates in various ways to the sonification of data and audio-based techniques for maintaining peripheral awareness.

A novel neural model made up of two self-organizing map nets --- one on top of the other --- is introduced and analysed experimentally. The model makes an effective use of context information, and that enables it to perform sequence classification and discrimination efficiently. It was successfully applied to real sequences, taken from the third voice of the sixteenth four-part fugue in G minor of the Well-Tempered Clavier (vol. I) of J. S. Bach. The model has application in domains which require pattern recognition, or more specifically, which demand recognizing either a set of sequences of vectors in time or sub-sequences into a unique and large sequence of vectors in time. 1 Introduction Several researchers have extended the Kohonen's self-organizing feature map model [1] to recognize sequential information. The problem involves either recognizing a set of sequences of vectors in time or recognizing sub-sequences inside a large and unique sequence. Some approaches are described be...

Much of the literature on time inconsistency has studied the external commitment devices that individuals use to address their self-control problems: tying oneself to the mast, staying away from temptation, holding illiquid assets, or “asking for controls ” from others. This paper, by contrast, focuses on internal commitment mechanisms or personal rules (diets, exercise regimens, resolutions, moral or religious precepts, etc.) through which people attempt to achieve self— discipline. The basic idea, which builds on Ainslie (1992), is that rules cause lapses to be interpreted as precedents, resulting in a loss of self—reputation which has an adverse impact on future self— control. We thus model the behavior of individuals who are unsure of their willpower (ability to delay gratiÞcation) in certain states of the world, and characterize feasible rules as (Markovian) self—reputational equilibria where impulses for immediate gratiÞcation are held in check by the fear of “losing faith in oneself ” —which would lead to a further collapse of self—discipline. We then examine how equilibrium conduct reßects the extent to which the individual’s self—monitoring is subject to opportunistic distortions of memory or inference, such as selectively recalling or Þnding excuses for one’s past behavior.