Publications

2023

October

1. Exploring the Effectiveness of Web-Based Programming Environments for MOOCs: A Comparative Study of CodeOcean and OpenJupyter

   Mohamed Elhayany , Sebastian Serth, and Christoph Meinel

   In 2023 IEEE Learning with MOOCS (LWMOOCS) , Oct 2023

   Abs Bib Website

   Programming courses offered by openHPI, the European MOOC platform of the Hasso Plattner Institute, feature hands-on programming exercises to support learners in practicing the newly acquired skills. These exercises are facilitated by two tools: CodeOcean and OpenJupyter. CodeOcean is user-friendly and suitable for beginners, while OpenJupyter is more advanced and used in data science courses. In this paper, we compare and discuss the advantages and limitations of both tools, providing recommendations for instructors and researchers in programming courses. We also address technical details, such as scalability and execution environments. Furthermore, we explore future research possibilities, particularly in learner collaboration and automated feedback. Our work supports learners in acquiring knowledge and testing it at their own pace, with individualized feedback and minimal technical requirements, contributing to an open education landscape in programming education.

   @inproceedings{elhayany_exploring_2023,
     address = {Cambridge, MA, USA},
     title = {Exploring the {Effectiveness} of {Web}-{Based} {Programming} {Environments} for {MOOCs}: {A} {Comparative} {Study} of {CodeOcean} and {OpenJupyter}},
     isbn = {9798350315592},
     shorttitle = {Exploring the {Effectiveness} of {Web}-{Based} {Programming} {Environments} for {MOOCs}},
     doi = {10.1109/LWMOOCS58322.2023.10306228},
     language = {en},
     urldate = {2023-11-10},
     booktitle = {2023 {IEEE} {Learning} with {MOOCS} ({LWMOOCS})},
     publisher = {IEEE},
     author = {Elhayany, Mohamed and Serth, Sebastian and Meinel, Christoph},
     month = oct,
     year = {2023},
     pages = {1--6}
   }

2. Design Principals for Building a Collaborative Exchange Platform for Auto-gradable Programming Exercises

   Sebastian Serth, Karen Schmieden , Mohamed Elhayany , Zuhra Sofyan , and Christoph Meinel

   e-learning and education, Oct 2023

   URN: urn:nbn:de:0009-5-57791

   Abs Bib Website

   The emergence of Massive Open Online Courses (MOOCs) has made computer science more accessible by offering courses on various programming languages and technologies to anyone with an internet connection. These MOOCs have demonstrated that providing learners with the necessary tools for self-regulated learning and formative feedback remains crucial to ensuring successful learning outcomes. Similar to MOOC learners, university and high-school students also benefit from interactive exercises and automated feedback. However, university lecturers and especially high-school teachers often lack access to suitable programming tasks and the necessary tools. Therefore, we started working on CodeHarbor, an innovative tool designed explicitly for teachers to share, rate, and discuss auto-gradable programming exercises with their colleagues. In this article, we describe the use of interviews and thematic analyses to examine the problem space and opportunity areas experienced by computer science educators who engage in exchanging digital teaching materials for their classes. As a result, we defined twelve user stories and three design principles that should be considered when developing a platform for exchanging computer science teaching materials. With collaborative authoring tools designed primarily for computer science teachers, we envision CodeHarbor to become an important tool to make computer science education more interactive and enjoyable.

   @article{serth_design_2023,
     title = {Design {Principals} for {Building} a {Collaborative} {Exchange} {Platform} for {Auto}-gradable {Programming} {Exercises}},
     volume = {15},
     issn = {1860-7470},
     language = {en},
     number = {2},
     journal = {e-learning and education},
     author = {Serth, Sebastian and von Schmieden, Karen and Elhayany, Mohamed and Sofyan, Zuhra and Meinel, Christoph},
     editor = {Lucke, Ulrike and Knoth, Alexander and Wilhelm-Weidner, Arno},
     month = oct,
     year = {2023},
     note = {URN: urn:nbn:de:0009-5-57791},
     keywords = {MOOC, programming, Auto-Grader, Benutzer:innenerfahrung, Code Repository, Code-Repository, e-learning, Exercises, Gemeinsame Nutzung, MOOCs, Programmierung, Sharing, Übungen, User Experience}
   }

August

1. On the Feasibility of Serverless Functions in the Context of Auto-Graders

   Sebastian Serth, Maximilian Paß , and Christoph Meinel

   In 2023 IEEE 2nd German Education Conference (GECon) , Aug 2023

   Abs Bib Website

   Learners interested in acquiring fundamental programming skills may choose from a variety of different offers, including Massive Open Online Courses (MOOCs). Usually, these courses not only include lecture videos and multiple-choice quizzes, but also feature hands-on programming exercises, allowing learners to apply their newly acquired knowledge right away. Since solving these exercises requires access to a programming tool chain, most MOOCs embed their exercises in a web-based environment supplying necessary tools. One of these so-called auto-graders is CodeOcean, which allows learners to write and run code or receive automated feedback. While a web-based auto-grader lowers the entry barrier for learners to get started, providing sufficient resources for all code executions poses an additional challenge for the MOOC provider, especially during high-demand periods. Therefore, we evaluated serverless functions as offered by cloud computing providers for the use in autograders and conducted a Randomized Control Trial. Although serverless functions at first appear to be slower compared to our existing containerized execution of learners’ code, they convinced with more constant execution times in high-demand periods.

   @inproceedings{serth_feasibility_2023,
     address = {Berlin, Germany},
     title = {On the {Feasibility} of {Serverless} {Functions} in the {Context} of {Auto}-{Graders}},
     isbn = {9798350348132},
     doi = {10.1109/GECon58119.2023.10295106},
     language = {en},
     urldate = {2023-11-10},
     booktitle = {2023 {IEEE} 2nd {German} {Education} {Conference} ({GECon})},
     publisher = {IEEE},
     author = {Serth, Sebastian and Paß, Maximilian and Meinel, Christoph},
     month = aug,
     year = {2023},
     pages = {1--6}
   }

July

1. On Air: Benefits of weekly Podcasts accompanying Online Courses

   Daniel Köhler , Sebastian Serth, and Christoph Meinel

   In Proceedings of the Tenth ACM Conference on Learning @ Scale , Jul 2023

   Abs Bib Website

   Podcasts are a widely-used medium for communication and learning. One advantage of them is the possibility to pursue other activities while listening. Contrasting, Massive Open Online Courses (MOOCs) employ video-based teaching methods. Current research, however, challenges the interactivity and variation of teaching content in established MOOCs. This manuscript presents an experiment conducted with a podcast series deployed alongside a MOOC on cybersecurity. In our Static-Group Comparison, we identified a significant increase in learning success in weekly graded exercises (6.3%) and the course’s final examination (6.4%) for learners exposing themselves to the podcast. Our first study results are promising in favor of multimedia learning. Hence, we present ideas for additional analysis and briefly outline which aspects of the results should be discussed in more depth.

   @inproceedings{kohler_air_2023,
     address = {Copenhagen, Denmark},
     title = {On {Air}: {Benefits} of weekly {Podcasts} accompanying {Online} {Courses}},
     copyright = {All rights reserved},
     isbn = {9798400700255},
     doi = {10.1145/3573051.3596178},
     language = {en},
     urldate = {2023-07-19},
     booktitle = {Proceedings of the {Tenth} {ACM} {Conference} on {Learning} @ {Scale}},
     publisher = {ACM},
     author = {Köhler, Daniel and Serth, Sebastian and Meinel, Christoph},
     month = jul,
     year = {2023},
     pages = {311--315}
   }

June

1. A Metastandard for the International Exchange of MOOCs: The MOOChub as First Prototype

   Thomas Staubitz , Sebastian Serth, Max Thomas , Markus Ebner , Markus Koschutnig-Ebner , Florian Rampelt , Alexander Stetten , and Andreas Wittke

   In Proceedings of the 8th European MOOC Stakeholder Summit (EMOOCs 2023) , Jun 2023

   Abs Bib Website

   The MOOChub is a joined web-based catalog of all relevant German and Austrian MOOC platforms that lists well over 750 Massive Open Online Courses (MOOCs). Automatically building such a catalog requires that all partners describe and publicly offer the metadata of their courses in the same way. The paper at hand presents the genesis of the idea to establish a common metadata standard and the story of its subsequent development. The result of this effort is, first, an open-licensed de-facto-standard, which is based on existing commonly used standards and second, a first prototypical platform that is using this standard: the MOOChub, which lists all courses of the involved partners. This catalog is searchable and provides a more comprehensive overview of basically all MOOCs that are offered by German and Austrian MOOC platforms. Finally, the upcoming developments to further optimize the catalog and the metadata standard are reported.

   @inproceedings{staubitz_metastandard_2023,
     address = {Potsdam, Germany},
     title = {A {Metastandard} for the {International} {Exchange} of {MOOCs}: {The} {MOOChub} as {First} {Prototype}},
     copyright = {Creative Commons Attribution 4.0 International},
     shorttitle = {A metastandard for the international exchange of {MOOCs}},
     doi = {10.25932/PUBLISHUP-62415},
     language = {en},
     urldate = {2024-02-05},
     booktitle = {Proceedings of the 8th {European} {MOOC} {Stakeholder} {Summit} ({EMOOCs} 2023)},
     author = {Staubitz, Thomas and Serth, Sebastian and Thomas, Max and Ebner, Markus and Koschutnig-Ebner, Markus and Rampelt, Florian and von Stetten, Alexander and Wittke, Andreas},
     month = jun,
     year = {2023},
     keywords = {000 Informatik, Informationswissenschaft, allgemeine Werke},
     pages = {147--161}
   }

May

1. Scale Up Multilingualism in Health Emergency Learning: Developing an Automated Transcription and Translation Tool

   Heini Utunen , Thomas Staubitz , Richelle George , Yu (Ursula) Zhao , Sebastian Serth, and Anna Tokar

   In Caring is Sharing – Exploiting the Value in Data for Health and Innovation , May 2023

   Abs Bib Website

   World Health Organization’s (WHO) emergency learning platform OpenWHO provided by Hasso Plattner Institut (HPI) delivered online learning in real-time and in multiple languages during the COVID-19 pandemic. The challenge was to move from manual transcription and translation to automated to increase the speed and quantity of materials and languages available. TransPipe tool was introduced to facilitate this task. We describe the TransPipe development, analyze its functioning and report key results achieved. TransPipe successfully connects existing services and provides a suitable workflow to create and maintain video subtitles in different languages. By the end of 2022, the tool transcribed nearly 4,700 minutes of video content and translated 1,050,700 characters of video subtitles. Automated transcription and translation have enormous potential as a public health learning tool, allowing the near-simultaneous availability of video subtitles on OpenWHO in many languages, thus improving the usability of the learning materials in multiple languages for wider audiences.

   @inproceedings{utunen2023transpipe,
     address = {Gothenburg, Sweden},
     series = {Studies in {Health} {Technology} and {Informatics}},
     title = {Scale {Up} {Multilingualism} in {Health} {Emergency} {Learning}: {Developing} an {Automated} {Transcription} and {Translation} {Tool}},
     volume = {302},
     copyright = {All rights reserved},
     isbn = {978-1-64368-388-1},
     doi = {10.3233/SHTI230162},
     language = {en},
     booktitle = {Caring is {Sharing} – {Exploiting} the {Value} in {Data} for {Health} and {Innovation}},
     publisher = {IOS Press},
     author = {Utunen, Heini and Staubitz, Thomas and George, Richelle and Zhao, Yu (Ursula) and Serth, Sebastian and Tokar, Anna},
     editor = {Hägglund, Maria and Blusi, Madeleine and Bonacina, Stefano and Nilsson, Lina and Madsen, Inge Cort and Pelayo, Sylvia and Moen, Anne and Benis, Arriel and Lindsköld, Lars and Gallos, Parisis},
     month = may,
     year = {2023},
     pages = {408--412}
   }

March

1. Metastandard für den internationalen Austausch von MOOCs – der MOOChub als erster Prototyp

   Martin Ebner , Markus Koschutnig-Ebner , Florian Rampelt , Sebastian Serth, Thomas Staubitz , Alexander Stetten , Max Thomas , and Andreas Wittke

   Zeitschrift für Hochschulentwicklung, Mar 2023

   Publisher: Verlag der Technischen Universität Graz & Verein Forum neue Medien in der Lehre Austria

   Abs Bib Website

   Der MOOChub ist eine Webseite, die weit über 700 Massive Open Online Courses (MOOCs) aus dem deutschsprachigen Raum von insgesamt neun unterschiedlichen Partner:innen listet. Damit eine solche Seite automatisiert aufgebaut werden kann, ist es notwendig, dass alle Partner:innen die Metadaten der Kurse in gleicher Weise beschreiben und verfügbar machen. Dieser Artikel beschreibt zunächst die Entstehung der Idee eines gemeinsamen Standards und wie dieser im Anschluss entwickelt worden ist. Das Ergebnis ist einerseits ein offen lizenzierter Quasi-Standard, der sich an üblichen Standards orientiert, und ein erster Prototyp, der sogenannte MOOChub, auf dem nun alle Kurse auffindbar und durchsuchbar sind. Abschließend wird über die nächsten möglichen und auch notwendigen Entwicklungen berichtet, die die Schnittstelle weiter optimieren sollen.

   @article{ebner_metastandard_2023,
     series = {Massive {Open} {Online} {Courses} und ihre {Rolle} in der digitalen ({Hochschul}-){Lehre}},
     title = {Metastandard für den internationalen {Austausch} von {MOOCs} – der {MOOChub} als erster {Prototyp}},
     volume = {18},
     copyright = {All rights reserved},
     issn = {2219-6994},
     doi = {10.3217/ZFHE-18-01/02},
     language = {de},
     number = {1},
     urldate = {2023-02-21},
     journal = {Zeitschrift für Hochschulentwicklung},
     author = {Ebner, Martin and Koschutnig-Ebner, Markus and Rampelt, Florian and Serth, Sebastian and Staubitz, Thomas and von Stetten, Alexander and Thomas, Max and Wittke, Andreas},
     editor = {Ebner, Martin and Staubitz, Thomas and Koschutnig-Ebner, Markus and Serth, Sebastian},
     month = mar,
     year = {2023},
     note = {Publisher: Verlag der Technischen Universität Graz \& Verein Forum neue Medien in der Lehre Austria},
     pages = {17--35}
   }

2. Editorial: Massive Open Online Courses und ihre Rolle in der digitalen (Hochschul-)Lehre

   Martin Ebner , Thomas Staubitz , Markus Koschutnig-Ebner , and Sebastian Serth

   Zeitschrift für Hochschulentwicklung, Mar 2023

   Publisher: Verlag der Technischen Universität Graz & Verein Forum neue Medien in der Lehre Austria

   Abs Bib Website

   Massive Open Online Courses, kurz MOOCs, sind Online-Kurse mit einer großen Zahl an Teilnehmer:innen, die zumeist auf speziellen Plattformen kostenlos zur Verfügung gestellt werden. Mit dem Kurs zur Künstlichen Intelligenz von Sebastian Thrun mit über 160.000 Lernenden fanden MOOCs zunehmend Verbreitung. Spätestens seit der COVID19-Pandemie sind sie nicht mehr aus unserem universitären Hochschulalltag wegzudenken und heute zum Teil integraler Bestandteil von Lehrveranstaltungen. Durch vielfältige Einsatzmöglichkeiten werden so Weiterbildungen, Workshops oder joint lectures unterstützt. Das aktuelle Themenheft rief zu Beiträgen rund um MOOCs auf und erlaubt dadurch einen Einblick in die facettenreichen Entwicklungen. In der aktuellen Ausgabe finden Sie hierzu spannende Beiträge mit Erfahrungsberichten, neuesten Erkenntnissen, Weiterentwicklungen und didaktischen Einsatzmöglichkeiten. Wir laden Sie also herzlich ein, mit uns gemeinsam dieses innovative, zukunftsträchtige und auch nachhaltige Thema weiter zu vertiefen.

   @article{ebner_editorial_2023,
     series = {Massive {Open} {Online} {Courses} und ihre {Rolle} in der digitalen ({Hochschul}-){Lehre}},
     title = {Editorial: {Massive} {Open} {Online} {Courses} und ihre {Rolle} in der digitalen ({Hochschul}-){Lehre}},
     volume = {18},
     copyright = {All rights reserved},
     issn = {2219-6994},
     doi = {10.3217/ZFHE-18-01/01},
     language = {de},
     number = {1},
     urldate = {2023-02-21},
     journal = {Zeitschrift für Hochschulentwicklung},
     author = {Ebner, Martin and Staubitz, Thomas and Koschutnig-Ebner, Markus and Serth, Sebastian},
     editor = {Ebner, Martin and Staubitz, Thomas and Koschutnig-Ebner, Markus and Serth, Sebastian},
     month = mar,
     year = {2023},
     note = {Publisher: Verlag der Technischen Universität Graz \& Verein Forum neue Medien in der Lehre Austria},
     pages = {9--15}
   }

3. Massive Open Online Courses und ihre Rolle in der digitalen (Hochschul-)Lehre

   Mar 2023

   doi: 10.3217/ZFHE-18-01

   Abs Bib Website

   Massive Open Online Courses, kurz MOOCs, sind Online-Kurse mit einer großen Zahl an Teilnehmer:innen, die zumeist auf speziellen Plattformen kostenlos zur Verfügung gestellt werden. Mit dem Kurs zur Künstlichen Intelligenz von Sebastian Thrun mit über 160.000 Lernenden fanden MOOCs zunehmend Verbreitung. Spätestens seit der COVID-19-Pandemie sind sie nicht mehr aus unserem universitären Hochschulalltag wegzudenken und heute zum Teil integraler Bestandteil von Lehrveranstaltungen. Durch vielfältige Einsatzmöglichkeiten werden so Weiterbildungen, Workshops oder joint lectures unterstützt. Das aktuelle Themenheft rief zu Beiträgen rund um MOOCs auf und erlaubt dadurch einen Einblick in die facettenreichen Entwicklungen. In der aktuellen Ausgabe finden Sie hierzu spannende Beiträge mit Erfahrungsberichten, neuesten Erkenntnissen, Weiterentwicklungen und didaktischen Einsatzmöglichkeiten. Wir laden Sie also herzlich ein, mit uns gemeinsam dieses innovative, zukunftsträchtige und auch nachhaltige Thema weiter zu vertiefen.

   @book{ebner_massive_2023,
     address = {Graz, Austria},
     series = {Massive {Open} {Online} {Courses} und ihre {Rolle} in der digitalen ({Hochschul}-){Lehre}},
     title = {Massive {Open} {Online} {Courses} und ihre {Rolle} in der digitalen ({Hochschul}-){Lehre}},
     volume = {1},
     copyright = {All rights reserved},
     isbn = {978-3-7519-0089-8},
     language = {de},
     number = {18},
     urldate = {2023-02-21},
     publisher = {Verlag der Technischen Universität Graz \& Verein Forum neue Medien in der Lehre Austria},
     editor = {Ebner, Martin and Staubitz, Thomas and Koschutnig-Ebner, Markus and Serth, Sebastian},
     month = mar,
     year = {2023},
     note = {doi: 10.3217/ZFHE-18-01}
   }

January

1. The mysterious adventures of Detective Duke: How storified programming MOOCs support learners in achieving their learning goals

   Christiane Hagedorn , Sebastian Serth, and Christoph Meinel

   Frontiers in Education, Jan 2023

   Abs Bib Website

   About 15 years ago, the first Massive Open Online Courses (MOOCs) appeared and revolutionized online education with more interactive and engaging course designs. Yet, keeping learners motivated and ensuring high satisfaction is one of the challenges today’s course designers face. Therefore, many MOOC providers employed gamification elements that only boost extrinsic motivation briefly and are limited to platform support. In this article, we introduce and evaluate a gameful learning design we used in several iterations on computer science education courses. For each of the courses on the fundamentals of the Java programming language, we developed a self-contained, continuous story that accompanies learners through their learning journey and helps visualize key concepts. Furthermore, we share our approach to creating the surrounding story in our MOOCs and provide a guideline for educators to develop their own stories. Our data and the long-term evaluation spanning over four Java courses between 2017 and 2021 indicates the openness of learners toward storified programming courses in general and highlights those elements that had the highest impact. While only a few learners did not like the story at all, most learners consumed the additional story elements we provided. However, learners’ interest in influencing the story through majority voting was negligible and did not show a considerable positive impact, so we continued with a fixed story instead. We did not find evidence that learners just participated in the narrative because they worked on all materials. Instead, for 10–16% of learners, the story was their main course motivation. We also investigated differences in the presentation format and concluded that several longer audio-book style videos were most preferred by learners in comparison to animated videos or different textual formats. Surprisingly, the availability of a coherent story embedding examples and providing a context for the practical programming exercises also led to a slightly higher ranking in the perceived quality of the learning material (by 4%). With our research in the context of storified MOOCs, we advance gameful learning designs, foster learner engagement and satisfaction in online courses, and help educators ease knowledge transfer for their learners.

   @article{hagedorn_mysterious_2023,
     series = {A {Paradigm} {Shift} in {Designing} {Education} {Technology} for {Online} {Learning}: {Opportunities} and {Challenges}},
     title = {The mysterious adventures of {Detective} {Duke}: {How} storified programming {MOOCs} support learners in achieving their learning goals},
     volume = {7},
     copyright = {All rights reserved},
     issn = {2504-284X},
     shorttitle = {The mysterious adventures of {Detective} {Duke}},
     doi = {10.3389/feduc.2022.1016401},
     urldate = {2023-01-12},
     journal = {Frontiers in Education},
     author = {Hagedorn, Christiane and Serth, Sebastian and Meinel, Christoph},
     editor = {Gamage, Dilrukshi},
     month = jan,
     year = {2023},
     pages = {1016401}
   }

2022

October

1. Measuring the effects of course modularizations in online courses for life-long learners

   Sebastian Serth, Thomas Staubitz , Martin Elten , and Christoph Meinel

   Frontiers in Education, Oct 2022

   Abs Bib Website

   Many participants in Massive Open Online Courses are full-time employees seeking greater flexibility in their time commitment and the available learning paths. We recently addressed these requirements by splitting up our 6-week courses into three 2-week modules followed by a separate exam. Modularizing courses offers many advantages: Shorter modules are more sustainable and can be combined, reused, and incorporated into learning paths more easily. Time flexibility for learners is also improved as exams can now be offered multiple times per year, while the learning content is available independently. In this article, we answer the question of which impact this modularization has on key learning metrics, such as course completion rates, learning success, and no-show rates. Furthermore, we investigate the influence of longer breaks between modules on these metrics. According to our analysis, course modules facilitate more selective learning behaviors that encourage learners to focus on topics they are the most interested in. At the same time, participation in overarching exams across all modules seems to be less appealing compared to an integrated exam of a 6-week course. While breaks between the modules increase the distinctive appearance of individual modules, a break before the final exam further reduces initial interest in the exams. We further reveal that participation in self-paced courses as a preparation for the final exam is unlikely to attract new learners to the course offerings, even though learners’ performance is comparable to instructor-paced courses. The results of our long-term study on course modularization provide a solid foundation for future research and enable educators to make informed decisions about the design of their courses.

   @article{serth_measuring_2022,
     title = {Measuring the effects of course modularizations in online courses for life-long learners},
     volume = {7},
     copyright = {All rights reserved},
     issn = {2504-284X},
     doi = {10.3389/feduc.2022.1008545},
     urldate = {2022-11-01},
     journal = {Frontiers in Education},
     author = {Serth, Sebastian and Staubitz, Thomas and van Elten, Martin and Meinel, Christoph},
     editor = {Gamage, Dilrukshi},
     month = oct,
     year = {2022},
     pages = {1008545}
   }

September

1. Integrating Podcasts into MOOCs: Comparing Effects of Audio- and Video-Based Education for Secondary Content

   Daniel Koehler , Sebastian Serth, Hendrik Steinbeck , and Christoph Meinel

   In Educating for a New Future: Making Sense of Technology-Enhanced Learning Adoption (EC-TEL 2022) , Sep 2022

   Abs Bib Website

   Multimedia learning methods can enrich any online learning scenario. However, traditional Massive Open Online Courses (MOOCs) often put the learner into classroom-like situations without considerably varying presentation formats. By conducting a study and analysis of multimedia elements such as interviews and podcasts, we lay a foundation for future research in the field of multimedia learning. This research studies video-based and audio-based education methods for secondary learning content. We explore both the conscious and subconscious effects of the different formats. In our quantitative assessment of more than 900 learners, we did not observe any significant differences in quiz performance between learners of the two groups. Although our recurring learners are used to video-based learning methods, the audio-based teaching methods were accepted and rated “easy to follow” by more than 80% of our learners. However, we observe that the learners enjoy traditional podcasts with a single presenter the least. Our work adds to the field of multimedia online teaching and shows that enriching courses with audio-based education methods proves beneficial for asynchronous learning offers.

   @inproceedings{koehler_integrating_2022,
     address = {Toulouse, France},
     title = {Integrating {Podcasts} into {MOOCs}: {Comparing} {Effects} of {Audio}- and {Video}-{Based} {Education} for {Secondary} {Content}},
     volume = {13450},
     copyright = {All rights reserved},
     isbn = {978-3-031-16289-3 978-3-031-16290-9},
     shorttitle = {Integrating {Podcasts} into {MOOCs}},
     doi = {10.1007/978-3-031-16290-9_10},
     language = {en},
     booktitle = {Educating for a {New} {Future}: {Making} {Sense} of {Technology}-{Enhanced} {Learning} {Adoption} ({EC}-{TEL} 2022)},
     publisher = {Springer},
     author = {Koehler, Daniel and Serth, Sebastian and Steinbeck, Hendrik and Meinel, Christoph},
     editor = {Hilliger, Isabel and Muñoz-Merino, Pedro J. and Laet, Tinne De and Ortega-Arranz, Alejandro and Farrell, Tracie},
     month = sep,
     year = {2022},
     pages = {131--144}
   }

July

1. Breaking the Ice? How to Foster the Sense of Community in MOOCs

   Christiane Hagedorn , Sebastian Serth, and Christoph Meinel

   In 2022 International Conference on Advanced Learning Technologies (ICALT) , Jul 2022

   Abs Bib Website

   Massive Open Online Courses (MOOCs) are usually attended by several thousand learners who barely get to know each other during the course period. Being unaware of fellow learners often results in a low sense of community. In addition, many MOOC learners are afraid of using the course forum, which often is the only participation opportunity in social course activities apart from forming smaller learning groups. Thus, learners can easily be frustrated with the course content when feeling alone. To improve social presence and the sense of community, course instructors can use ice-breaking games. First, this paper evaluates which kind of ice-breaking games can be used in MOOCs. Afterward, we present the results from a first experiment where we use “self-reflection sociograms as an icebreaking activity. Most learners perceived the implemented Self-Reflection Questionnaires” (SRQ) ice-breaker as a positive course feature (68.35%). SRQs increased the sense of community, and learners were satisfied (91.06%) with their perceived community sense level. The SRQs were also helpful for the teaching teams. Our results indicate that further investigation of SRQs is beneficial to explore the provided value for course instructors and their influence on individual MOOC learners and community-building.

   @inproceedings{hagedorn_breaking_2022,
     address = {Bucharest, Romania},
     title = {Breaking the {Ice}? {How} to {Foster} the {Sense} of {Community} in {MOOCs}},
     copyright = {All rights reserved},
     isbn = {978-1-66549-519-6},
     shorttitle = {Breaking the {Ice}?},
     doi = {10.1109/ICALT55010.2022.00013},
     language = {en},
     urldate = {2022-08-19},
     booktitle = {2022 {International} {Conference} on {Advanced} {Learning} {Technologies} ({ICALT})},
     publisher = {IEEE},
     author = {Hagedorn, Christiane and Serth, Sebastian and Meinel, Christoph},
     month = jul,
     year = {2022},
     pages = {22--26}
   }

June

1. Analysis of the Applicability of General Scaling Laws on Course Size, Completion Rates, and Forum Activity in MOOCs

   Thomas Staubitz , Max Bothe , Mohamed Elhayany , Christiane Hagedorn , Sebastian Serth, Theresa Zobel , and Christoph Meinel

   In Proceedings of the Ninth ACM Conference on Learning @ Scale , Jun 2022

   Abs Bib Website

   In 2017, Geoffrey West published his book "Scale" in which he examined universal laws of scale in different contexts. Inspired by his keynote in 2021’s Learning@Scale conference, we investigated the applicability of these laws in the context of Massive Open Online Courses and learners’ behavior. We tested these laws on different learning platforms from academic, enterprise and social, and research contexts. In this paper, we examine course characteristics, such as course size, the completion rate, and the forum activity. We observed that the number of issued certificates scales almost identically on all examined platforms, while forum participation scales slightly different on each of the platforms. In the future, we will perform a deeper analysis on the forum behavior that exceeds a mere quantitative analysis.

   @inproceedings{staubitz_analysis_2022,
     address = {New York City NY USA},
     title = {Analysis of the {Applicability} of {General} {Scaling} {Laws} on {Course} {Size}, {Completion} {Rates}, and {Forum} {Activity} in {MOOCs}},
     copyright = {Creative Commons Namensnennung - Nicht kommerziell - Keine Bearbeitungen 4.0 Internationale Lizenz (CC-BY-NC-ND)},
     isbn = {978-1-4503-9158-0},
     doi = {10.1145/3491140.3528310},
     language = {en},
     urldate = {2022-07-07},
     booktitle = {Proceedings of the {Ninth} {ACM} {Conference} on {Learning} @ {Scale}},
     publisher = {ACM},
     author = {Staubitz, Thomas and Bothe, Max and Elhayany, Mohamed and Hagedorn, Christiane and Serth, Sebastian and Zobel, Theresa and Meinel, Christoph},
     month = jun,
     year = {2022},
     pages = {294--298}
   }

2021

November

1. Consuming Security: Evaluating Podcasts to Promote Online Learning Integrated with Everyday Life

   Daniel Koehler , Sebastian Serth, and Christoph Meinel

   In 2021 World Engineering Education Forum/Global Engineering Deans Council (WEEF/GEDC) , Nov 2021

   Abs Bib Website

   Traditional (online) teaching approaches put the student into a video-based, classroom-like situation. When asked to reproduce the content, the student can consciously remember what he learned and answer accordingly. Contrasting, knowledge of IT-security aspects requires sensitization for the topic throughout the daily life of a learner. We learned from interactions with former learners that they sometimes found themselves in situations where they - despite knowing better - still behaved in an undesired way. We thereby conclude that the classroom-based presentation of knowledge in Massive Open Online Courses (MOOCs) is not sufficient for the field of IT-Security Education. Therefore, this work presents an approach to a study to assess and analyze different audio-based methods of conveying knowledge, which can integrate into a learner’s everyday life. In the spirit of Open Research, we therefore publish our research questions and chosen methods in order to discuss these within the community. Following, we will study the perception of the proposed education methods by learners and suggest possible improvements for subsequent research.

   @inproceedings{koehler_consuming_2021,
     address = {Madrid, Spain},
     title = {Consuming {Security}: {Evaluating} {Podcasts} to {Promote} {Online} {Learning} {Integrated} with {Everyday} {Life}},
     copyright = {All rights reserved},
     isbn = {978-1-66542-488-2},
     shorttitle = {Consuming {Security}},
     doi = {10.1109/WEEF/GEDC53299.2021.9657464},
     language = {English},
     urldate = {2022-02-11},
     booktitle = {2021 {World} {Engineering} {Education} {Forum}/{Global} {Engineering} {Deans} {Council} ({WEEF}/{GEDC})},
     publisher = {IEEE},
     author = {Koehler, Daniel and Serth, Sebastian and Meinel, Christoph},
     month = nov,
     year = {2021},
     pages = {476--481}
   }

October

1. Improving the Scalability and Security of Execution Environments for Auto-Graders in the Context of MOOCs

   Sebastian Serth, Daniel Köhler , Leonard Marschke , Felix Auringer , Konrad Hanff , Jan-Eric Hellenberg , Tobias Kantusch , Maximilian Paß , and Christoph Meinel

   In Proceedings of the Fifth Workshop "Automatische Bewertung von Programmieraufgaben" (ABP 2021) , Oct 2021

   Abs Bib Website

   Learning a programming language requires learners to write code themselves, execute their programs interactively, and receive feedback about the correctness of their code. Many approaches with so-called auto-graders exist to grade students’ submissions and provide feedback for them automatically. University classes with hundreds of students or Massive Open Online Courses (MOOCs) with thousands of learners often use these systems. Assessing the submissions usually includes executing the students’ source code and thus implies requirements on the scalability and security of the systems. In this paper, we evaluate different execution environments and orchestration solutions for auto-graders. We compare the most promising open-source tools regarding their usability in a scalable environment required for MOOCs. According to our evaluation, Nomad, in conjunction with Docker, fulfills most requirements. We derive implications for the productive use of Nomad for an auto-grader in MOOCs.

   @inproceedings{serth_improving_2021,
     address = {Virtual Event, Germany},
     title = {Improving the {Scalability} and {Security} of {Execution} {Environments} for {Auto}-{Graders} in the {Context} of {MOOCs}},
     volume = {5},
     copyright = {All rights reserved},
     doi = {10.18420/abp2021-1},
     language = {en},
     booktitle = {Proceedings of the {Fifth} {Workshop} "{Automatische} {Bewertung} von {Programmieraufgaben}" ({ABP} 2021)},
     publisher = {Gesellschaft für Informatik e.V. (GI)},
     author = {Serth, Sebastian and Köhler, Daniel and Marschke, Leonard and Auringer, Felix and Hanff, Konrad and Hellenberg, Jan-Eric and Kantusch, Tobias and Paß, Maximilian and Meinel, Christoph},
     editor = {Greubel, André and Strickroth, Sven and Striewe, Michael},
     month = oct,
     year = {2021},
     pages = {3--10}
   }

June

1. TransPipe - A Pipeline for Automated Transcription and Translation of Videos

   Joseph Bethge , Sebastian Serth, Thomas Staubitz , Tobias Wuttke , Oliver Nordemann , Partha-Pratim Das , and Christoph Meinel

   In Proceedings of the 7th European MOOC Stakeholder Summit (EMOOCs 2021) , Jun 2021

   Abs Bib Website

   Online learning environments, such as Massive Open Online Courses (MOOCs), often rely on videos as a major component to convey knowledge. However, these videos exclude potential participants who do not understand the lecturer’s language, regardless of whether that is due to language unfamiliarity or aural handicaps. Subtitles and/or interactive transcripts solve this issue, ease navigation based on the content, and enable indexing and retrieval by search engines. Although there are several automated speech-to-text converters and translation tools, their quality varies and the process of integrating them can be quite tedious. Thus, in practice, many videos on MOOC platforms only receive subtitles after the course is already finished (if at all) due to a lack of resources. This work describes an approach to tackle this issue by providing a dedicated tool, which is closing this gap between MOOC platforms and transcription and translation tools and offering a simple workflow that can easily be handled by users with a less technical background. The proposed method is designed and evaluated by qualitative interviews with three major MOOC providers.

   @inproceedings{bethge_transpipe_2021,
     address = {Potsdam, Germany},
     title = {{TransPipe} - {A} {Pipeline} for {Automated} {Transcription} and {Translation} of {Videos}},
     doi = {10.25932/publishup-51694},
     language = {en},
     booktitle = {Proceedings of the 7th {European} {MOOC} {Stakeholder} {Summit} ({EMOOCs} 2021)},
     publisher = {Universitätsverlag Potsdam},
     author = {Bethge, Joseph and Serth, Sebastian and Staubitz, Thomas and Wuttke, Tobias and Nordemann, Oliver and Das, Partha-Pratim and Meinel, Christoph},
     month = jun,
     year = {2021},
     pages = {79--94}
   }

2. Impact of Contextual Tips for Auto-Gradable Programming Exercises in MOOCs

   Sebastian Serth, Ralf Teusner , and Christoph Meinel

   In Proceedings of the Eighth ACM Conference on Learning @ Scale , Jun 2021

   Abs Bib Website

   Learners in Massive Open Online Courses offering practical programming exercises face additional challenges next to the actual course content. Beginners have to find approaches to deal with misconceptions and often struggle with the correct syntax while solving the exercises. The paper at hand presents insights from offering contextual tips in a web-based development environment used for practical programming exercises. We measured the effects of our approach in a Python course with 6,000 active students in a hidden A/B test and additionally used qualitative surveys. While a majority of learners valued the assistance, we were unable to show a direct impact on completion rates or average scores. We however noticed that users requesting tips took significantly longer and made more use of other assistance features of the platform than users in our control group. Insights from our study can be used to target beginners with more specific hints and provide additional, context-specific clues as part of the learning material.

   @inproceedings{serth_impact_2021,
     address = {Virtual Event, Germany},
     title = {Impact of {Contextual} {Tips} for {Auto}-{Gradable} {Programming} {Exercises} in {MOOCs}},
     copyright = {All rights reserved},
     isbn = {978-1-4503-8215-1},
     doi = {10.1145/3430895.3460166},
     language = {en},
     urldate = {2021-06-09},
     booktitle = {Proceedings of the {Eighth} {ACM} {Conference} on {Learning} @ {Scale}},
     publisher = {ACM},
     author = {Serth, Sebastian and Teusner, Ralf and Meinel, Christoph},
     month = jun,
     year = {2021},
     pages = {307--310}
   }

March

1. CodeOcean and CodeHarbor: Auto-Grader and Code Repository

   Sebastian Serth, Thomas Staubitz , Ralf Teusner , and Christoph Meinel

   In SPLICE 2021 workshop CS Education Infrastructure for All III: From Ideas to Practice , Mar 2021

   Abs Bib Website

   The Hasso Plattner Institute (HPI) successfully operates a MOOC (Massive Open Online Course) platform since 2012. Since 2013, global enterprises, international organizations, governments, and research projects funded by the German ministry of education are partnering with us to operate their own instances of the platform. The focus of our platform instance is on IT topics, which includes programming courses in different programming languages. An important element of these courses are graded hands-on programming assignments. MOOCs, even more than traditional classroom situations, depend on automated solutions to assess programming exercises. Manual evaluation is not an option due to the massive amount of users that participate in these courses. The paper at hand presents two of the tools developed in this context at the HPI: CodeOcean—an auto-grader for a variety of programming languages, and CodeHarbor, a tool to share auto-gradable programming exercises between various online platforms.

   @inproceedings{serth_codeocean_2021,
     address = {Virtual Event},
     title = {{CodeOcean} and {CodeHarbor}: {Auto}-{Grader} and {Code} {Repository}},
     copyright = {All rights reserved},
     language = {en},
     booktitle = {{SPLICE} 2021 workshop {CS} {Education} {Infrastructure} for {All} {III}: {From} {Ideas} to {Practice}},
     author = {Serth, Sebastian and Staubitz, Thomas and Teusner, Ralf and Meinel, Christoph},
     month = mar,
     year = {2021},
     pages = {5}
   }

2020

September

1. Digitale Arbeitsblätter mit interaktiven Programmieraufgaben im Informatik-Unterricht

   Sebastian Serth, Ralf Teusner , and Christoph Meinel

   In Lecture Notes in Informatics (LNI) - Proceedings: DELFI 2020 – Die 18. Fachtagung Bildungstechnologien der Gesellschaft für Informatik e.V. , Sep 2020

   Abs Bib Website

   Moderner Informatikunterricht umfasst das Erlernen von Grundlagen des Programmierens. Dabei verwenden Lehrer häufig bereits vorhandene Videos, Quizfragen und praktische Programmieraufgaben aus Massive Open Online Courses (MOOCs), obwohl derzeit die Möglichkeiten zur Anpassung der Inhalte und dem Hinzufügen eigener Materialien für Lehrer begrenzt sind. Unsere Software ermöglicht es Lehrern, ihre eigenen interaktiven Arbeitsblätter mit angepassten und eigenen Übungen zu erstellen. Im Rahmen einer praktischen Evaluierung wurde das Konzept von Schülern und Lehrern gleichermaßen gut angenommen: Lehrer hatten mehr Zeit für die Beantwortung individueller Fragen und Schüler konnten in ihrem eigenen Tempo mithilfe automatisierter Rückmeldungen lernen. Für die Vorbereitung zukünftiger Unterrichtsstunden schätzten Lehrer die Möglichkeit, häufige Fehler auszuwerten, um so zuvor unerkannte Probleme besprechen zu können. Interaktive Arbeitsblätter fördern individualisierte Lernprozesse, unterstützen Lehrer in der Unterrichtsgestaltung und sind somit ein wichtiger Bestandteil digitaler Bildung an Schulen.

   @inproceedings{serth_digitale_2020,
     address = {Bonn, Germany},
     series = {Lecture {Notes} in {Informatics}},
     title = {Digitale {Arbeitsblätter} mit interaktiven {Programmieraufgaben} im {Informatik}-{Unterricht}},
     volume = {P-308},
     copyright = {All rights reserved},
     isbn = {978-3-88579-702-9},
     language = {de},
     booktitle = {Lecture {Notes} in {Informatics} ({LNI}) - {Proceedings}: {DELFI} 2020 – {Die} 18. {Fachtagung} {Bildungstechnologien} der {Gesellschaft} für {Informatik} e.{V}.},
     publisher = {Gesellschaft für Informatik e.V. (GI)},
     author = {Serth, Sebastian and Teusner, Ralf and Meinel, Christoph},
     editor = {Zender, Raphael and Ifenthaler, Dirk and Leonhardt, Thiemo and Schumacher, Clara},
     month = sep,
     year = {2020},
     keywords = {sys:relevantfor:its myown webuniversity},
     pages = {235--246}
   }

2019

October

1. Evaluating Digital Worksheets with Interactive Programming Exercises for K-12 Education

   Sebastian Serth, Ralf Teusner , Jan Renz , and Matthias Uflacker

   In 2019 IEEE Frontiers in Education Conference (FIE) , Oct 2019

   Abs Bib Website

   This Research Full Paper presents insights from digital worksheets with embedded interactive programming exercises tailored for high-school students new to programming. Computer Science teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers’ options to adapt the content to their specific needs are currently limited. Based on a qualitative survey with thirteen teachers, we developed a software prototype which allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights by providing results from automated submission analysis, thus uncovering knowledge gaps and fostering content-driven in-class discussions. Our evaluation shows that the concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.

   @inproceedings{serth_evaluating_2019,
     address = {Cincinnati, OH, USA},
     title = {Evaluating {Digital} {Worksheets} with {Interactive} {Programming} {Exercises} for {K}-12 {Education}},
     isbn = {978-1-72811-746-1},
     doi = {10.1109/FIE43999.2019.9028680},
     language = {English},
     booktitle = {2019 {IEEE} {Frontiers} in {Education} {Conference} ({FIE})},
     publisher = {IEEE},
     author = {Serth, Sebastian and Teusner, Ralf and Renz, Jan and Uflacker, Matthias},
     month = oct,
     year = {2019},
     pages = {1--9}
   }

2. Integrating Professional Tools in Programming Education with MOOCs

   Sebastian Serth

   In 2019 IEEE Frontiers in Education Conference (FIE) , Oct 2019

   Abs Bib Website

   An increasing number of high school teachers use existing Massive Open Online Courses (MOOCs) concerning programming education. Most MOOCs focus on teaching the basics of a programming language and common concepts or patterns. MOOC platforms usually provide their own code execution environments and thus have full control over the features and appearance available to learners. However, only a subset of tools available to professional software engineers is used in introductory programming MOOCs. While the reduction of features is helpful to ease navigation for novices, we assume that learners benefit from more advanced features at a later stage in the learning process. To help students minimize bugs and conceptual mistakes, we intend to evaluate how pair programming could be enabled for remote peers in MOOCs with a synchronized editor and an additional communication channel. Further, we plan to use static program analysis to get more insights about the code written by learners and to provide early feedback about the coding style. One of our contributions will be to identify possibilities to integrate professional tools and methods in MOOCs supported by an evaluation from learners.

   @inproceedings{serth_integrating_2019,
     address = {Cincinnati, OH, USA},
     title = {Integrating {Professional} {Tools} in {Programming} {Education} with {MOOCs}},
     copyright = {All rights reserved},
     isbn = {978-1-72811-746-1},
     doi = {10.1109/FIE43999.2019.9028643},
     language = {English},
     booktitle = {2019 {IEEE} {Frontiers} in {Education} {Conference} ({FIE})},
     author = {Serth, Sebastian},
     month = oct,
     year = {2019},
     pages = {2}
   }

May

1. Individual Worksheets with Interactive Programming Exercises within the HPI Schul-Cloud

   Sebastian Serth

   Hasso Plattner Institute, University of Potsdam , May 2019

   Abs Bib Website

   Modern computer science education in high-schools requires students to learn the basics of programming. In terms of content, teachers often incorporate existing videos, quizzes, and practical programming exercises from Massive Open Online Courses (MOOCs). However, teachers’ options to adapt the content to their specific needs or to add their own material are currently limited. Based on a qualitative survey with thirteen teachers, we developed tools to extend these options. Our software prototype allows teachers to create their own interactive worksheets consisting of texts, videos, quizzes, and practical programming exercises. Additionally, teachers can embed and further customize existing exercises from MOOCs. Further, we enable teachers to gain deeper insights into the learning progress of their students by providing results from automated submission analysis. These data allow uncovering potential knowledge gaps and foster content-driven in-class discussions. In this thesis, we present findings from an evaluation with different school classes using our software. The concept was well received by students and teachers alike: Teachers noticed the possibility of a shift in their role from a lecturing instructor to an individual tutor, as students are enabled to learn at their own pace and receive specific, direct feedback based on automated unit tests. For the preparation of upcoming lessons, teachers valued the ability to analyze common mistakes of their students to uncover and discuss previously hidden problems. Interactive worksheets, as an integrated part of digital education, thus foster informed teacher interventions as part of an individualized student learning process.

   @mastersthesis{serth_individual_2019,
     address = {Potsdam, Germany},
     title = {Individual {Worksheets} with {Interactive} {Programming} {Exercises} within the {HPI} {Schul}-{Cloud}},
     language = {English},
     school = {Hasso Plattner Institute, University of Potsdam},
     author = {Serth, Sebastian},
     month = may,
     year = {2019}
   }

2018

June

1. VAMO — What story do you Want to Tell?

   Felipe Cabral , Simran Shah , Zhiheng Zhou , Sebastian Serth, Simon Krogmann , and Winfried Lötzsch

   Jun 2018

   Abs Bib Website

   As technology improves it becomes more and more present in our everyday lives. Artificial Intel- ligence (AI) is a field of research that has existed for the past sixty years but only recently has it become ubiquitous. In the current context we live in, AI is present in smartphones and many ap- plications we use daily from search engines to image processing to recommendation engines. AI is finishing our sentences and learning our taste. Our team, comprised of three graduate students from Stanford University and three from Hasso Plattner Institute (HPI), Potsdam, has been approached by FutureWei Technologies to enhance human communication with Artificial Intelligence.

   @techreport{cabral2018vamo,
     title = {{VAMO} --- {What} story do you {Want} to {Tell}?},
     copyright = {All rights reserved},
     institution = {Stanford University},
     author = {Cabral, Felipe and Shah, Simran and Zhou, Zhiheng and Serth, Sebastian and Krogmann, Simon and Lötzsch, Winfried},
     month = jun,
     year = {2018}
   }

2017

October

1. An Interactive Platform to Simulate Dynamic Pricing Competition on Online Marketplaces

   Sebastian Serth, Nikolai Podlesny , Marvin Bornstein , Jan Lindemann , Johanna Latt , Jan Selke , Rainer Schlosser , Martin Boissier , and Matthias Uflacker

   In 2017 IEEE 21st International Enterprise Distributed Object Computing Conference (EDOC) , Oct 2017

   Abs Bib Website

   E-commerce marketplaces are highly dynamic with constant competition. While this competition is challenging for many merchants, it also provides plenty of opportunities, e.g., by allowing them to automatically adjust prices in order to react to changing market situations. For practitioners however, testing automated pricing strategies is time-consuming and potentially hazardously when done in production. Researchers, on the other side, struggle to study how pricing strategies interact under heavy competition. As a consequence, we built an open continuous time framework to simulate dynamic pricing competition called Price Wars. The microservice-based architecture provides a scalable platform for large competitions with dozens of merchants and a large random stream of consumers. Our platform stores each event in a distributed log. This allows to provide different performance measures enabling users to compare profit and revenue of various repricing strategies in real-time. For researchers, price trajectories are shown which ease evaluating mutual price reactions of competing strategies. Furthermore, merchants can access historical marketplace data and apply machine learning. By providing a set of customizable, artificial merchants, users can easily simulate both simple rule-based strategies as well as sophisticated data-driven strategies using demand learning to optimize their pricing strategies.

   @inproceedings{serth_interactive_2017,
     address = {Quebec City, QC},
     title = {An {Interactive} {Platform} to {Simulate} {Dynamic} {Pricing} {Competition} on {Online} {Marketplaces}},
     isbn = {978-1-5090-3045-3},
     doi = {10.1109/EDOC.2017.17},
     urldate = {2019-02-08},
     booktitle = {2017 {IEEE} 21st {International} {Enterprise} {Distributed} {Object} {Computing} {Conference} ({EDOC})},
     publisher = {IEEE},
     author = {Serth, Sebastian and Podlesny, Nikolai and Bornstein, Marvin and Lindemann, Jan and Latt, Johanna and Selke, Jan and Schlosser, Rainer and Boissier, Martin and Uflacker, Matthias},
     month = oct,
     year = {2017},
     pages = {61--66}
   }

September

1. Enabling En-Route Filtering for End-to-End Encrypted CoAP Messages

   Klara Seitz , Sebastian Serth, Konrad-Felix Krentz , and Christoph Meinel

   In Proceedings of the 15th ACM Conference on Embedded Network Sensor Systems - SenSys ’17 , Sep 2017

   Bib Website

   @inproceedings{seitz_enabling_2017,
     address = {Delft, Netherlands},
     title = {Enabling {En}-{Route} {Filtering} for {End}-to-{End} {Encrypted} {CoAP} {Messages}},
     isbn = {978-1-4503-5459-2},
     doi = {10.1145/3131672.3136960},
     language = {en},
     urldate = {2019-02-08},
     booktitle = {Proceedings of the 15th {ACM} {Conference} on {Embedded} {Network} {Sensor} {Systems}  - {SenSys} '17},
     publisher = {ACM Press},
     author = {Seitz, Klara and Serth, Sebastian and Krentz, Konrad-Felix and Meinel, Christoph},
     month = sep,
     year = {2017},
     pages = {1--2}
   }

2. Serving Live Multimedia for the Linked Open Data Cloud

   Sebastian Serth, Stephan Haarmann , and Lukas Faber

   47. Jahrestagung der Gesellschaft fü Informatik, Informatik 2017, Chemnitz, Germany, Sep 2017

   Abs Bib Website

   DBpedia is a community-driven project to extract semantic data fromWikipedia articles. It publishes the results as RDF data in the Linked Open Data Cloud.With DBpedia Live, the community enabled live updates of linked data using the OAI-PMH protocol to receive and process changes on Wikipedia. The MediaWiki foundation discontinued their support for OAI-PMH in March 2016 causing DBpedia Live to no longer receive live updates. In this work, we use RCStream, the new MediaWiki protocol to notify other systems of changes, to re-enable live updates in DBpedia Live. Currently, users need to consume two DBpedia resources to access general information and multimedia files about one entity. On the one hand DBpedia holds the structured information. On the other DBpedia Commons holds most multimedia information. We improve the integration of multimedia data into DBpedia by introducing a new extractor to the DBpedia Extraction Framework that extracts most multimedia data from a Wikipedia page. Additionally, we present two further extractors that link pages in DBpedia with pages in DBpedia Commons and vice versa. All our changes are available in the DBpedia Extraction Framework and in use, e.g. for DBpedia Live.

   @article{serth_serving_2017,
     series = {{LNI}},
     title = {Serving {Live} {Multimedia} for the {Linked} {Open} {Data} {Cloud}},
     volume = {P-275},
     issn = {1617-5468},
     doi = {10.18420/in2017_252},
     language = {en},
     urldate = {2019-02-08},
     journal = {47. Jahrestagung der Gesellschaft fü Informatik, Informatik 2017, Chemnitz, Germany},
     author = {Serth, Sebastian and Haarmann, Stephan and Faber, Lukas},
     month = sep,
     year = {2017}
   }

August

1. Data-Driven Repricing Strategies in Competitive Markets: An Interactive Simulation Platform

   Martin Boissier , Rainer Schlosser , Nikolai Podlesny , Sebastian Serth, Marvin Bornstein , Johanna Latt , Jan Lindemann , Jan Selke , and Matthias Uflacker

   In Proceedings of the Eleventh ACM Conference on Recommender Systems - RecSys ’17 , Aug 2017

   Abs Bib Website

   Modern e-commerce platforms pose both opportunities as well as hurdles for merchants. While merchants can observe markets at any point in time and automatically reprice their products, they also have to compete simultaneously with dozens of competitors. Currently, retailers lack the possibility to test, develop, and evaluate their algorithms appropriately before releasing them into the real world. At the same time, it is challenging for researchers to investigate how pricing strategies interact with each other under heavy competition. To study dynamic pricing competition on online marketplaces, we built an open simulation platform. To be both flexible and scalable, the platform has a microservice-based architecture and handles large numbers of competing merchants and arriving consumers. It allows merchants to deploy the full width of pricing strategies, from simple rule-based strategies to more sophisticated data-driven strategies using machine learning. Our platform enables analyses of how a strategy’s performance is affected by customer behavior, price adjustment frequencies, the competitors’ strategies, and the exit/entry of competitors. Moreover, our platform allows to study the long-term behavior of self-adapting strategies.

   @inproceedings{boissier_data-driven_2017,
     address = {Como, Italy},
     title = {Data-{Driven} {Repricing} {Strategies} in {Competitive} {Markets}: {An} {Interactive} {Simulation} {Platform}},
     isbn = {978-1-4503-4652-8},
     shorttitle = {Data-{Driven} {Repricing} {Strategies} in {Competitive} {Markets}},
     doi = {10.1145/3109859.3109979},
     language = {en},
     urldate = {2019-02-08},
     booktitle = {Proceedings of the {Eleventh} {ACM} {Conference} on {Recommender} {Systems}  - {RecSys} '17},
     publisher = {ACM Press, New York, NY, USA},
     author = {Boissier, Martin and Schlosser, Rainer and Podlesny, Nikolai and Serth, Sebastian and Bornstein, Marvin and Latt, Johanna and Lindemann, Jan and Selke, Jan and Uflacker, Matthias},
     month = aug,
     year = {2017},
     pages = {355--357}
   }