miércoles, 19 de septiembre de 2007

A Framework for the Automatic Generation of Algorithm Animations Based on Design Techniques

L. Fernández-Muñoz, A. Pérez-Carrasco, J.Á. Velázquez-Iturbide, J. Urquiza-Fuentes. In Second European Conference on Technology Enhanced Learning (EC-TEL), 2007, Pages 475-480.

Abstract. A novel approach to algorithm animation consists in displaying algorithms based on their design technique. In this paper, we describe a framework to generate these animations without effort from the instructor. We describe a preprocessing phase that modifies the source code of the algorithm to visualize. When the transformed code is executed, a trace is stored and then used to generate an animation. We also describe the architecture of the animation subsystem. Finally, we outline the main features of SRec, a system that we have built to illustrate the feasibility of this approach. It is aimed at visualizing multiple views of recursion, namely traces, the control stack and activation trees.

miércoles, 18 de julio de 2007

Assessing the Usability of a Cookies-Based Access Monitoring Tool for a CMS

R. Hijón-Neira, J. Urquiza-Fuentes, F. Domínguez-Mateos, J.Á. Velázquez-Iturbide. In Seventh IEEE International Conference on Advanced Learning Technologies (ICALT) 2007, Pages 262-264

Abstract. We have developed several tools to allow instructors analyze students' interactions in a Course Management System. In this paper we describe a Systematic Usability Evaluation designed to test the usability of one of these tools. The evaluations were based on task analysis and follow-up studies. We have assessed effectiveness, efficiency, usefulness, ease of use, learnability, and user's satisfaction of the tool. In addition to regular observation and questionnaires, 3- scope video recording was used to provide the evaluator with more information about interactions. The use of this technology helped us in identifying functions and features that need improvement. We describe the three-step method that we have developed and the satisfactory results it has provided us.

miércoles, 23 de mayo de 2007

Human-Centered Aspects

Olga Kulyk, Robert Kosara, Jaime Urquiza and Ingo Wassink. In Human-Centered Visualization Environments, 2007, Pages 13-75

Abstract. Humans have remarkable perceptual capabilities. These capabilities are heavily underestimated in current visualizations. Often, this is due to the lack of an in-depth user study to set the requirements for optimal visualizations. The designer does not understand what kind of information should be visualized, how it should be presented or what kind of interactions should be supported. The key elements of successful information visualization are the correct data using the best visualization technique and the best interaction techniques with respect to users. If one of these elements is ignored, people might interpret the data in the wrong way and thus might not understand the underlying information or a pattern.

domingo, 4 de marzo de 2007

WinHIPE: an IDE for functional programming based on rewriting and visualization

C. Pareja-Flores, J. Urquiza-Fuentes, J.Á. Velázquez-Iturbide. ACM SIGPLAN Notices 42(3), 2007, Pages 14-23 

Abstract. The article describes an IDE for functional programming, called WinHIPE. It provides an interactive and flexible tracer, as well as a powerful visualization and animation system. The former tool is based on the rewriting model of evaluation, and the latter provides automatic generation of visualizations and animations, friendly support for customization, maintenance and exportation of animations to the Web, and facilities to cope with large scale. Its main advantage over other visualization systems is an effortless approach to animation creation and maintenance, based on generating visualizations and animations automatically, as a side effect of program execution. Finally, we briefly describe our experience using the system during several years in educational settings.
Open Access Archive at URJC

martes, 6 de febrero de 2007

An Evaluation of the Effortless Approach to Build Algorithm Animations with WinHIPE

J. Urquiza-Fuentes, J.Á. Velázquez-Iturbide. Electr. Notes Theor. Comput. Sci. 178, 2007, Pages 3-13 

Abstract. The use of algorithm visualizations in computer science education is not a new thing. Although there is a firm belief that graphical representations of algorithms are learning aids, empirical studies show that what is important is what the students do with the animations rather than what they see in them. In this paper we compare to kinds of interaction: viewing animations vs constructing animations. We have conducted a controlled experiment where a group of students (n=15) had to study an algorithm and complete a knowledge test about it and a subjective opinion questionnaire. Students were randomly divided in constructing and viewing groups. Results have been measured by means of learning outcomes, efficiency issues and student's subjective opinion. Results significantly evidence that builders obtained better results than viewers.
Open Access Archive at URJC