Gerald Futschek

Bebras International Contest on Informatics and Computer Literacy: Criteria for Good Tasks

The Bebras International Contest on Informatics and Computer Literacy is a motivation competition in informatics that addresses all lower and upper secondary school pupils divided into three age groups: Benjamin (age 11-14), Junior (age 15-16) and Senior (for upper secondary level). Using a computer the pupils have to solve 15 to 21 tasks of different levels within 45 minutes. Two general types of problems have been used: interactive tasks and multiple-choice tasks. Creating interesting and attractive tasks that are also motivating and funny for the pupils is very challenging. The paper deals with criteria for good tasks. Some examples of tasks are presented and discussed as well.

Algorithmic thinking: the key for understanding computer science

We show that algorithmic thinking is a key ability in informatics that can be developed independently from learning programming. For this purpose we use problems that are not easy to solve but have an easily understandable problem definition. A proper visualization of these problems can help to understand the basic concepts connected with algorithms: correctness, termination, efficiency, determinism, parallelism, etc. The presented examples were used by the author in a pre-university course, they may also be used in secondary schools to help understanding some concepts of computer science.

Learning algorithmic thinking with tangible objects eases transition to computer programming

Learning algorithmic thinking can start in early years and must be oriented on the thinking ability of young children. Suitable environments with tangible objects and easy to understand problems motivate the young to learn the first concepts of algorithms. We present in this paper a learning scenario Tim the Train for primary school children, that involves tangible objects and allows a variety of interesting tasks to learn basic concepts of algorithmic thinking. We also show how a smooth transition from a playful environment with tangible objects to a virtual Scratch/BYOB environment may help the young learners to learn their first steps in understanding virtual environments and programming concepts.

Bebras Contest and Digital Competence Assessment: Analysis of Frameworks

The article is made of two parts. The first part discusses the importance of informal education environments supported by IT/ICT in students’ learning, followed by reports of some international competitions and the role they have in improving students’ interest and use of Informatics and related disciplines. At the end of the section, it describes the Bebras contest, an international competition supporting students’ Information and Communication Technology competences with emphasis on cross discipline competences, which are useful to solve real life problems. In the second part of the article, the outcomes of a research study on the features of a framework for digital competence assessment are reported. Based on this, some criticisms emerging from the analysis of the answers that students gave to a questionnaire built on the guidelines of the mentioned framework are analysed. They are integrated by the comments that teachers, colleagues and researchers made on the structure of the hypothesized framework. At last, a new model for digital literacy assessment is proposed. In the conclusion, the necessary elements for making the last framework effective are outlined and its suitability for the construction of the yearly questionnaire of the Bebras contest is discussed.

Starting learning with computer controlled models

Computer controlled models provide an excellent situation for creative and explorative learning. The functionality and the limits of automata and machines can be explored and understood by building their models. The paper presents a didactic concept for starting learning with computer controlled models. We discuss the aspects of interdisciplinary learning combining the topics engineering, mechanics and information technology. Special attention is given to the first steps in learning the programming of computer controlled models. The chosen model allows a stepwise introduction of concepts without using step by step instructions. It supports creative ideas, even at the very beginning of learning. This paper is based on our experience in introducing computer controlled models to students of ages 9–16.

Student Retention: Towards Defining Measures for Improved Quality of Teaching and Learning in the First Year of Computer Science Studies

At the Faculty of Computer Science at the TU Wien, Vienna, Austria, the studies of computer science (CS) face two issues in the first year: a gender gap and a high student dropout rate. In order to tackle these problems, the faculty has set up a project called START Informatics to analyse the status quo, to identify potential pitfalls, to take actions and to develop measures to improve the quality of the first year of CS studies. Therefore, we will first examine the current situation in teaching with a mixed methods approach comprising lecture observations, student and teacher interviews and a large-scale questionnaire for first year students. As a result, the objective of the project is to describe recommendations and measures to improve the learning and teaching experience with a focus on student retention and potential gender issues.

Ein Modell zur stufenweisen Umsetzung von Software-Wiederverwendung in der Praxis

Zusammenfassung. Die Wiederverwendung bereits existierender Software verspricht sowohl höhere Produktivität als auch bessere Wartbarkeit und Produktqualität. In der industriellen und wirtschaftlichen Praxis anzutreffende Software ist allerdings schon innerhalb eines Unternehmens sehr heterogen. Sie variiert stark in Alter, Anwendungsgebiet, Dokumentationsgrad, verwendeter Entwicklungsumgebung und ist durch Programmierer mit unterschiedlichem Ausbildungsstand im Software-Engineering entstanden. Für die Einführung von Software-Wiederverwendung (Reuse) in der Praxis schlagen wir drei Entwicklungsstufen vor, die durch schrittweise steigende Investitionen von der Basis grundsätzlicher Wartbarkeit bis zu einer unternehmensweiten Reuse-Kultur führen. Das Modell baut auf Vorschlägen der Reuse-Forschung und unseren Erfahrungen mit zwei Beratungsprojekten aus der Praxis industrieller Software-Entwicklung im Bank- und Versicherungsbereich mit Rücksicht auf lokale Zeit- und Kostenbeschränkungen auf. Die für den Einsatz von Software-Wiederverwendung notwendigen Rollen der beteiligten Mitarbeiter und begleitende organisatorische Maßnahmen werden erklärt. Die erfolgreiche institutionalisierte Einführung von Wiederverwendung bedingt eine Anpassung der Unternehmenskultur, deren Verlauf sich mehr am Potential der vorhandenen Mitarbeiter orientieren muß als am Einsatz der neuesten Ideen von Methoden- oder Werkzeuganbietern.Abstract. Reuse of existing software can significantly increase productivity and provide higher maintainability as well as higher product quality. Existing software systems in industrial practice are usually very heterogeneous – even within the same company. The software varies in age, problem domain, level of documentation, used development environments as well as in levels of software engineering consciousness and skills among the involved software developers and maintainers. We describe a model for reuse that provides three levels of reuse intensities/investments designed to lead from basic maintainability to a company-wide reuse culture. The model is based on suggestions in state-of-the-art reuse research and our experiences in two consulting projects with in-house-developers in the banking and insurance industry to meet local constraints of time and costs. Important roles of personnel and accompanying organizational measures are explained. Successful introduction of institutionalized reuse needs a shaping of the corporate culture, which must be oriented towards enhancing the potential of employees rather than toward trying out the hottest ideas of method-consultants or tool-vendors.Key words: software reuse, maintainability, standards, quality assurance, management issues, introduction of reuseReuse of existing software can significantly increase productivity and provide higher maintainability as well as higher product quality. Existing software systems in industrial practice are usually very heterogeneous - even within the same company. The software varies in age, problem domain, level of documentation, used development environments as well as in levels of software engineering consciousness and skills among the involved software developers and maintainers. We describe a model for reuse that provides three levels of reuse intensities/investments designed to lead from basic maintainability to a company-wide reuse culture. The model is based on suggestions in state-of-the-art reuse research and our experiences in two consulting projects with in-house-developers in the banking and insurance industry to meet local constraints of time and costs. Important roles of personnel and accompanying organizational measures are explained. Successful introduction of institutionalized reuse needs a shaping of the corporate culture, which must be oriented towards enhancing the potential of employees rather than toward trying out the hottest ideas of method-consultants or tool-vendors.

Algebraic Properties of Loop Invariants

A set P(DO, R) of all invariants that ensure termination and where the postcondition R is true after termination is defined for every loop DO and for every postcondition R. Complying with the corresponding properties required, these sets P(DO, R) induce a topology on wp(DO, R). The weakest precondition wp(DO, R) is the weakest invariant of DO with respect to R. The topology P(DO, R) has a non-trivial structure and contains arbitrary conjunctions of invariants.

Die schwächste Precondition (weakest precondition)

Wir betrachten irgendein Programmstuck S und irgendeine Postcondition R und wollen eine passende Precondition Q ermitteln, sodas nach dem Start in einem Zustand aus Q das Programmstuck S in einem Zustand aus R terminiert.

Invertieren von Programmen

Ursprunglich war es nur eine interessante Aufgabe, Programme zu finden, die die Wirkung gegebener Programme wieder ruckgangig machen. Heute ist das systematische Invertieren von Programmen ein Werkzeug der Programmentwicklung geworden.