Ralf Teusner

Towards practical programming exercises and automated assessment in Massive Open Online Courses

In recent years, Massive Open Online Courses (MOOCs) have become a phenomenon presenting the prospect of free high class education to everybody. They bear a tremendous potential for teaching programming to a large and diverse audience. The typical MOOC components, such as video lectures, reading material, and easily assessable quizzes, however, are not sufficient for proper programming education. To learn programming, participants need an option to work on practical programming exercises and to solve actual programming tasks. It is crucial that the participants receive proper feedback on their work in a timely manner. Without a tool for automated assessment of programming assignments, the teaching teams would be restricted to offer optional ungraded exercises only. The paper at hand sketches scenarios how practical programming exercises could be provided and examines the landscape of potentially helpful tools in this context. Automated assessment has a long record in the history of computer science education. We give an overview of existing tools in this field and also explore the question what can and/or should be assessed.

openHPI - A case-study on the emergence of two learning communities

Recently a new format of online education has emerged that combines video lectures, interactive quizzes and social learning into an event that aspires to attract a massive number of participants. This format, referred to as Massive Open Online Course (MOOC), has garnered considerable public attention, and has been invested with great hopes (and fears) of transforming higher education by opening up the walls of closed institutions to a world-wide audience. In this paper, we present two MOOCs that were hosted at the same platform, and have implemented the same learning design. Due to their difference in language, topic domain and difficulty, the communities that they brought into existence were very different. We start by describing the MOOC format in more detail, and the distinguishing features of openHPI. We then discuss the literature on communities of practice and cultures of participation. After some statistical data about the first openHPI course, we present our qualitative observations about both courses, and conclude by giving an outlook on an ongoing comparative analysis of the two courses.

CodeOcean - A versatile platform for practical programming excercises in online environments

The paper at hand introduces CodeOcean, a web-based platform to provide practical programming exercises. CodeOcean is designed to be used in Massive Open Online Courses (MOOCs) to teach programming to beginners. Its concept and implementation are discussed with regard to tools provided to students and teachers, sandboxed and scalable code execution, scalable assessment, and interoperability. MOOCs bear a tremendous potential for teaching programming to a large and diverse audience. Learning to program, however, is a hands-on effort; watching videos and solving multiple choice tests will not be sufficient. A platform, such as CodeOcean, to work on practical programming exercises and to solve actual programming tasks is required. Due to the massiveness of the courses, teaching teams cannot check, give feedback, or assess the submissions of the participants manually. CodeOcean provides the participants with proper automated feedback in a timely manner and is able to assess the given programming tasks in an automated way.

Scaling youth development training in IT using an xMOOC platform

The paper at hand evaluates the Massive Open Online Course (MOOC) Spielend Programmieren Lernen (Playfully learning to program), an effort to scale the youth development program at the Hasso Plattner Institute (HPI) for a larger audience. The HPI has a strong tradition in attracting children and adolescents to take their first steps towards a career in IT at an early age. The Schülerakademie, the Schülerkolleg, the Schülerklub, and the support for the CoderDojo in Potsdam are some of the regular activities in this context to take youngsters by the hand and supply them with material and guidance in their mother tongue. With the emergence of MOOCs and the success of HPIs own MOOC Platform - openHPI - it was a natural step to develop a course to address an audience that is only marginally represented in openHPIs regular courses: school children and adolescents. A further novelty for openHPI in this course was the focus on teaching programming with a high percentage of obligatory hands-on tasks. Particularly for this course, a standalone tool allowing participants to write and evaluate code directly in the browser - without the need to install additional software - has been developed. We will compare this tool to a small selection of similar approaches on other platforms. As it will be shown, the course attracted a far more diverse audience than expected, and therefore, also needs to be seen in the context of spreading digital literacy amongst wider parts of society. In this context we also will discuss the significant differences in the usage of the forum between the course Spielend Programmieren Lernen and the course In-Memory Databases, a more traditional openHPI course.

Taking Informed Action on Student Activity in MOOCs

This paper presents a novel approach to understand specific student behavior in MOOCs. Instructors currently perceive participants only as one homogeneous group. In order to improve learning outcomes, they encourage students to get active in the discussion forum and remind them of approaching deadlines. While these actions are most likely helpful, their actual impact is often not measured. Additionally, it is uncertain whether such generic approaches sometimes cause the opposite effect, as some participants are bothered with irrelevant information. On the basis of fine granular events emitted by our learning platform, we derive metrics and enable teachers to employ clustering, in order to divide the vast field of participants into meaningful subgroups to be addressed individually.

Optimizing Routes of Public Transportation Systems by Analyzing the Data of Taxi Rides

Public transportation systems are flexible and affordable for the passengers. In contrast, the operation and construction of the necessary infrastructure is cost-intensive and requires extensive planning. Decisions about the scheduling, capacities and the location of stations are dependent on various economic, social, and environmental factors and have a major impact on the structure of a city. In this context, information about the starting points and destinations of potential passengers is highly relevant for operators. Unfortunately, the collection of this data is not trivial and often based on time intensive and expensive studies. In this paper we present a novel approach to gain knowledge for transportation system optimization based on the data of taxi rides, which have been recorded for documentation purposes. This data can be analyzed and offers an insight into the fine-grained travel intentions of millions of people. We introduce an interactive web application, which enables the analysis of about 700 millions taxi rides in New York City. Additionally to the exploration of the most frequent travel routes, the application can automatically suggest useful extensions of the exciting transportation system or suggest an optimized route map, which can be used to evaluate the existing one. With this functionality, the presented software effectively supports the decision processes of operators and enables the continuous evaluation of the existing systems.

Effects of automated interventions in programming assignments: evidence from a field experiment

A typical problem in MOOCs is the missing opportunity for course conductors to individually support students in overcoming their problems and misconceptions. This paper presents the results of automatically intervening on struggling students during programming exercises and offering peer feedback and tailored bonus exercises. To improve learning success, we do not want to abolish instructionally desired trial and error but reduce extensive struggle and demotivation. Therefore, we developed adaptive automatic just-in-time interventions to encourage students to ask for help if they require considerably more than average working time to solve an exercise. Additionally, we offered students bonus exercises tailored for their individual weaknesses. The approach was evaluated within a live course with over 5,000 active students via a survey and metrics gathered alongside. Results show that we can increase the call outs for help by up to 66% and lower the dwelling time until issuing action. Learnings from the experiments can further be used to pinpoint course material to be improved and tailor content to be audience specific.

Should I Bug You? Identifying Domain Experts in Software Projects Using Code Complexity Metrics

In any sufficiently complex software system there are experts, having a deeper understanding of parts of the system than others. However, it is not always clear who these experts are and which particular parts of the system they can provide help with. We propose a framework to elicit the expertise of developers and recommend experts by analyzing complexity measures over time. Furthermore, teams can detect those parts of the software for which currently no, or only few experts exist and take preventive actions to keep the collective code knowledge and ownership high. We employed the developed approach at a medium-sized company. The results were evaluated with a survey, comparing the perceived and the computed expertise of developers. We show that aggregated code metrics can be used to identify experts for different software components. The identified experts were rated as acceptable candidates by developers in over 90% of all cases.

Can MOOCs Support Secondary Education in Computer Science

Despite the importance of competencies in computer science for participation in the digital transformation of nearly all sectors, there is still a lack of learning material and technically experienced teachers in German schools. In the paper at hand, we investigate the potential of Massive Open Online Courses (MOOCs) for secondary education. Schools can profit from this learning content and format provided by well-known institutions. However, German schools provide some challenging conditions, which have to be taken into account for a meaningful integration of e-learning elements. Our statistical and qualitative results are based on the representative data of the National Educational Panel Study (NEPS), the learning data of more than 100,000 online learners from over 150 countries, and the outcomes of several workshops with teachers and school administrators.

Cellular Automata as basis for programming exercises in a MOOC on Test Driven Development

Programming tasks are an important part of teaching computer programming as they foster students to develop essential programming skills and techniques through practice. The design of educational problems plays a crucial role in the extent to which the experiential knowledge is imparted to the learner both in terms of quality and quantity. Badly designed tasks have been known to put-off students from practicing programming. Hence, there is a need for carefully designed problems. Cellular Automata programming lends itself as a very suitable candidate among problems designed for programming practice. In this paper we describe how various types of problems can be designed using concepts from Cellular Automata and discuss the features which make them good practice problems with regard to instructional pedagogy. We also present a case study on a Cellular Automata programming exercise used in a MOOC on Test Driven Development using JUnit, and discuss the automated evaluation of code submissions and the feedback about the reception of this exercise by participants in this course.