Glenn Rowe

ARAUCARIA: SOFTWARE FOR ARGUMENT ANALYSIS, DIAGRAMMING AND REPRESENTATION

Argumentation theory involves the analysis of naturally occurring argument, and one key tool employed to this end both in the academic community and in teaching critical thinking skills to undergraduates is argument diagramming. By identifying the structure of an argument in terms of its constituents and the relationships between them, it becomes easier to critically evaluate each part of an argument in turn. The task of analysis and diagramming, however, is labor intensive and often idiosyncratic, which can make academic exchange difficult. The Araucaria system provides an interface which supports the diagramming process, and then saves the result using AML, an open standard, designed in XML, for describing argument structure. Araucaria aims to be of use not only in pedagogical situations, but also in support of research activity. As a result, it has been designed from the outset to handle more advanced argumentation theoretic concepts such as schemes, which capture stereotypical patterns of reasoning. The software is also designed to be compatible with a number of applications under development, including dialogic interaction and online corpus provision. Together, these features, combined with its platform independence and ease of use, have the potential to make Araucaria a valuable resource for the academic community.

TOPALi: software for automatic identification of recombinant sequences within DNA multiple alignments

SUMMARY TOPALi is a new Java graphical analysis application that allows the user to identify recombinant sequences within a DNA multiple alignment (either automatically or via manual investigation). TOPALi allows a choice of three statistical methods to predict the positions of breakpoints due to past recombination. The breakpoint predictions are then used to identify putative recombinant sequences and their relationships to other sequences. In addition to its sophisticated interface, TOPALi can import many sequence formats, estimate and display phylogenetic trees and allow interactive analysis and/or automatic HTML report generation. AVAILABILITY TOPALi is freely available from http://www.bioss.ac.uk/software.html

Difficulties in Learning and Teaching Programming—Views of Students and Tutors

We have conducted a web-based questionnaire on the various concepts and topics of object-oriented programming that students on introductory courses found most difficult to cope with.A statistical analysis of our results shows that those topics that rely on a clear understanding of pointers and memory-related concepts (such as copy constructors and virtual functions) prove to be the most difficult. In other words, we believe these concepts are only hard because of the students inability to comprehend what is happening to their program in memory, as they are incapable of creating a clear mental model of its execution.These results would suggest that a clearer approach to teaching these topics would be beneficial to students. We are currently working on a visualization-based approach to address these issues.

The essential properties of evolutionary stability

We show that the “standard conditions” for evolutionarily stable strategies proposed by Maynard Smith & Price (1973) are sometimes inconsistent with the notion of dynamic stability. We suggest, therefore, that the criteria of dynamic stability should be used in place of the standard conditions in assessing stability in phenotypic models of evolution. Strategy mixtures satisfying the condition of dynamic stability are termed evolutionarily stable points. An algorithm is presented which will locate all evolutionarily stable points for any discrete, linear contest.

PASS: an automated system for program assessment

Abstract This paper describes PASS (Program Assessment using Specified Solutions), a software system which is used to assess C programs produced by students on an introductory programming course. In programming, it is possible to solve problems in many ways; some good, some bad. The majority of program assessment systems, to date, assess programs by either script based methods, which verify the correct output, or by program metrics, such as cyclomatic complexity. Neither of these methods takes into account the way in which a problem has been solved. Each will generate equal marks for both good and bad programs, provided they produce the correct output. PASS takes into account the way in which a problem is solved by performing a comparison of the submitted program with a solution plan, which is provided by the course tutor. A mark and feedback, based on how well the submitted program corresponds to the tutors valid solution, is then returned by the system.

A computer based learning system for teaching computing: implementation and evaluation

Abstract A computer-based learning (CBL) system has been an integral part of first- and second-year computing courses at the University of Dundee for several years. The system uses the World Wide Web (WWW) for its implementation, and includes question–answer tutorials, programming tutorials, and animated demonstrations. Here, we report on an evaluation of the system as used in the second-year class. Improvements to the system as a result of the evaluation have been undertaken, and these are described in the second Section.

Argument Diagramming: The Araucaria Project

Formal arguments, such as those used in science, medicine and law to establish a conclusion by providing supporting evidence, are frequently represented by diagrams such as trees and graphs. We describe the software package Araucaria which allows textual arguments to be marked up and represented as standard, Toulmin or Wigmore diagrams. Since each of these diagramming techniques was devised for a particular domain or argumentation, we discuss some of the issues involved in translating between diagrams. The exercise of translating between different diagramming types illustrates that any one diagramming system often cannot capture all of the nuances inherent in an argument. Finally, we describe some areas, such as critical thinking courses in colleges and universities and the analysis of evidence in court cases, where Araucaria has been put to practical use.

Formative Automated Computer Testing (FACT)

This study describes the context for the development of a tool to formatively assess information technology skills of students. The tool provides a reliable and valid assessment of word processing competency, utilizing automation to apply the test instrument via the Microsoft Office package. Tests can be designed directly by tutors, and delivered via a network. Evaluation of the tests suggests that immediate automated testing is preferred by students compared to a traditional written test. There is evidence that the tool improves the IT skills of its users, whereas a traditional written test has no such beneficial effect.

To each genotype a separate strategy--a dynamic game theory model of a general diploid system.

A dynamic game theory model is presented for a diploid system in which each genotype corresponds to a different strategy. The population mates randomly and the strategy, which is determined by a single locus, is expressed only in the male. A general analytic solution for any number of alleles does not appear to be possible, but the cases of two and three alleles are treated in detail. A stability analysis applicable to any number of alleles is presented, so that any equilibria located by numerical methods can be checked for local stability. Computer programs for doing all of these calculations are available from the author.

Mutations, mixed strategies and game theory

The effects of incorporating mutation and mixed strategies on the location and stability of evolutionarily stable points (ESPs) in game theory models of evolution are examined by means of numerical simulation. It is found that mutation can change the location and stability of equilibria. An easily programmable method for determining these effects explicitly is given.