Mark Ratcliffe

Putting threshold concepts into context in computer science education

This paper describes Threshold Concepts, a theory of learning that distinguishes core concepts whose characteristics can make them troublesome in learning. With an eye to applying this theory in computer science, we consider this notion in the context of related topics in computer science education.

Can graduating students design software systems

This paper examines software designs produced by students nearing completion of their Computer Science degrees. The results of this multi-national, multi institutional experiment present some interesting implications for educators.

Scaffolding with object diagrams in first year programming classes: some unexpected results

This paper reports on an experiment in which first year programming students were given explicit encouragement to use Object (Instance) diagrams when tracing code in multiple-choice questions. We conjectured that by providing scaffolding in this technique, students would be helped to understand the code better and that they would then continue to draw their own diagrams in similar situations. This turned out not to be the case. Although generally students who draw diagrams do better in questions that test their understanding of code behaviour and object referencing, our intervention does not appear to have helped students and the students who were exposed to the intervention were not more likely to go on to use the technique themselves.

Dora: a structure-oriented environment generator

This paper describes a generic structure-oriented environment that has been developed as part of the ESPRIT-funded Dragon project. The environment can be instantiated by a tool builder to provide a multiple view structure editor for a particular language or method. This environment kernel is particularly important for two reasons: the environment is composed of an interacting hierarchy of editors, each acting on appropriate components of the target structure; and for each of these ‘substructure’ editors, it is possible that the developer can specify many different views, and that these views are independent within the same editing pane.

Learning computer science: perceptions, actions and roles

This phenomenographic study opens the classroom door to investigate teachers’ experiences of students learning difficult computing topics. Three distinct themes are identified and analysed. Why do students succeed or fail to learn these concepts? What actions do teachers perceive will ameliorate the difficulties facing students? Who is responsible, and for what, in the learning situation? Theoretical work on threshold concepts and conceptual change deals with mechanisms and processes associated with learning difficult material [Meyer, J. and Land, R., 2005. Threshold concepts and troublesome knowledge (2): epistemological considerations and a conceptual framework for teaching and learning. Higher Education, 49 (3), 373–388; Entwistle, N., 2007. Conceptions of learning and the experience of understanding: thresholds, contextual influences, and knowledge objects. In: S. Vosniadou, A. Baltas and X. Vamvakoussi, eds. Re-framing the conceptual change approach in learning and instruction. Amsterdam, The Netherlands: Elsevier, chap. 11]. With this work as a background, we concentrate on the perceptions of teachers. Where do teachers feel that the difficulties lie when studying the troublesome knowledge in computing? Student and teacher-centric views of teaching reported in other literature are also to be seen in our results. The first two categories in the ‘what’ and ‘who’ themes are teacher-centric. Higher level categories in all themes show increasingly learner centred conceptions of the instructional role. However, the nature of the categories in the ‘why’ theme reveals a new dimension dealing with teacher beliefs specific to the nature of troublesome knowledge in computing. A number of prior studies in tertiary teaching concentrate on approaches to teaching [Trigwell, K. and Prosser, M., 2004. Development and use of the approaches to teaching inventory. Educational Psychology Review, 16 (4), 409–424], and attitudes to scholarship of teaching and learning [Ashwin, P. and Trigwell, K., 2004. Investigating educational development. In: Making sense of staff and educational development, 117–131]. Our focus on learning difficult topics extends this work, investigating teacher conceptions of causality in relation to learning difficulties. We argue that teacher conceptions of enabling factors, for learning difficult computing topics, can act to limit the nature and scope of academics’ pedagogical responses. Improved awareness of teachers beliefs regarding student learning difficulties both extends and complements existing efforts to develop a more student-centred computing pedagogy.

Extreme programming promotes extreme learning

Extreme programming (XP) is an agile methodology claimed to promote the rapid development of software systems, enabling the accommodation of changing customer requirements during the project lifecycle without excessive cost penalties. The mechanisms used to achieve this require the software development team to maintain accurate tacit knowledge through extensive face-to-face communication and peer learning. This characteristic of XP, the authors argue, makes it a suitable tool in the teaching of new technologies to software engineering students. This is borne out by feedback from a group of fourth-year Master of Engineering (MEng) software engineering undergraduate students who undertook an XP-based project as part of their course. Furthermore, the authors argue that the methodology is best taught in its full form through group project work. This is most effective when undertaken in the latter years of a computer science or software engineering course, after the students have been exposed to more traditional, plan-based methodologies.

Categorizing student software designs: Methods, results, and implications

This paper examines the problem of studying and comparing student software designs. We propose semantic categorization as a way to organize widely varying data items. We describe how this was used to organize a particular multi-national, multi-institutional dataset, and present the results of this analysis: most students are unable to effectively design software. We examine how these designs vary with different academic and demographic factors, and discuss the implications of this work on both education and education research.

Software component interface description for reuse

This paper describes the background and development of a component interface description language called the Component Interface Descriptor (CIDER). CIDER is an object-oriented design language, which enables a software engineer to capture, integrate and reuse component interfaces based on a model of the reusable software component, the 3C model. The 3C model of the reusable component is named after the three attributes of the component that the model describes; its Context, Concept and Content.

From Troubleshooting to Process Design: Closing the Manufacturing Loop

This paper describes the dual use of a case base for diagnosis and for improving the design of a manufacturing process. In the short term, the case base is used to provide past experience in dealing with similar problems during the manufacture of aluminum components. In the longer term, it is used to feed that experience into the design of the manufacturing process for new components.

Improving the tutoring of software design using case-based reasoning

Abstract Judging by results, the methods undertaken to teach software development to large classes of students are flawed; too many students are failing to grasp any real understanding of programming and software design. To address this problem the University of Wales, Aberystwyth has developed VorteX, an interactive collaborative design tool that captures the design processes of novice students, provides a diagnosis system capable of interpreting the students’ work, and advises on their design process. This paper provides an overview of VorteX, its capabilities and use, and explains how the case-based system identifies redundancies in the storage of student designs and reduces data volume. The paper describes how equivalence maps merge similar classes to reduce the design structure possibilities, how snippets eliminate the replication of components and how abstract snippets represent the design intent of students in a minimalist form. Finally it concludes with comments on the student experience of the VorteX case-based reasoning assistant.