Gerd Kortemeyer

Peer-Reviewed Journal Publications

  1. M. Teresa Peña, Peter U. Sauer, Alfred Stadler, and Gerd Kortemeyer, Three-nucleon force and the Delta-mechanism for pion production and pion absorption, Phys. Rev. C 48(5), 2208 — 2221 (1993)
    The description of the three-nucleon system in terms of nucleon and Δ degrees of freedom is extended to allow for explicit pion production (absorption) from single dynamic Δ deexcitation (excitation) processes. This mechanism yields an energy dependent effective three-body Hamiltonian. The Faddeev equations for the trinucleon bound state are solved with a force model that has already been tested in the two-nucleon system above pion-production threshold. The binding energy and other bound-state properties are calculated. The contribution to the effective three-nucleon force arising from the pionic degrees of freedom is evaluated. The validity of previous coupled-channel calculations with explicit but stable Δ isobar components in the wave function is studied.
  2. Gerd Kortemeyer, Wolfgang Bauer, Kevin Haglin, Joelle Murray, and Scott Pratt, Causality Violations in Cascade Models of Nuclear Collisions, Phys. Rev. C 52(5), 2714 — 2724 (1995)
    Transport models have successfully described many aspects of intermediate energy heavy-ion collision dynamics. As the energies increase in these models to the ultrarelativistic regime, Lorentz covariance and causality are not strictly respected. The standard argument is that such effects are not important to final results; but they have not been seriously considered at high energies. We point out how and why these happen, how serious of a problem they may be and suggest ways of reducing or eliminating the undesirable effects.
  3. Gerd Kortemeyer, Frank Daffin, and Wolfgang Bauer, Nuclear Flow in Consistent Boltzmann Algorithm Models, Phys. Lett. B 374(1‐3), 25 — 30 (1996)
    We investigate the stochastic Direct Simulation Monte Carlo method (DSMC) for numerically solving the collision-term in heavy-ion transport theories of the Boltzmann-Uehling-Uhlenbeck (BUU) type. The first major modification we consider is changes in the collision rates due to excluded volume and shadowing/screening effects (Enskog theory). The second effect studied by us is the inclusion of an additional advection term. These modifications ensure a non-vanishing second virial and change the equation of state for the scattering process from that of an ideal gas to that of a hard-sphere gas. We analyse the effect of these modifications on the calculated value of directed nuclear collective flow in heavy ion collisions, and find that the flow slightly increases.
  4. Gerd Kortemeyer, Wolfgang Bauer, and Gerd J. Kunde, Isospin dependent multi-fragmentation in 112Sn+112Sn and 124Sn+124Sn collisions, Phys. Rev. C 55(5), 2730 — 2733 (1997)
    Significant differences in the relationships between fragment, neutron, and charged particle multiplicities were found between 112Sn+112Sn and 124Sn+124Sn collisions at 40 MeV/A. In this paper we explore the possibility to explain this phenomenon in the framework of percolation models, and find that the results are only reproducible in part.
  5. Klaus Morawetz, Václav Spivcka, Pavel Lipavsky, Gerd Kortemeyer, Christiane Kuhrts, and Regina Nebauer, Virial corrections to simulations of heavy ion reaction, , Phys. Rev. Lett. 82(19), 3767 — 3770 (1999)
    Within quantum molecular dynamics (QMD) simulations we demonstrate the effect of virial corrections on heavy ion reactions. Unlike in standard codes, the binary collisions are treated as nonlocal so that the contribution of the collision flux to the reaction dynamics is covered. A comparison with standard QMD simulations shows that the virial corrections lead to a broader proton distribution bringing theoretical spectra closer towards experimental values. Complementary Boltzmann-Uehling-Uhlenbeck simulations reveal that the nonlocality enhances the collision rate in the early stage of the reaction. It suggests that the broader distribution appears due to an enhanced preequilibrium emission of particles.
  6. Gerd Kortemeyer and Wolfgang Bauer, Multimedia Collaborative Content Creation (mc3) - the MSU LectureOnline System, Journal of Engineering Education 88(4), 421 — 427 (1999)
    Putting lecture material on_line is a time_consuming undertaking. Before communicating any subject matter, faculty must invest time and effort in dealing with computer_related administrative overhead. Also, in traditional lecture preparations, faculty can profit from years of previously prepared written material, while for on_line classes, they often unnecessarily re_create learning modules that already exist on_line. Lecture Online is a means for faculty to develop modular on_line resources collaboratively and share them with each other. The Learning Online Network, which is currently under development, implements a distributed server network with a strong emphasis on cross_institutional collaborations with intellectual property rights management and optional usage_based royalty mechanisms.
  7. Gerd Kortemeyer, Matthew Hall, Joyce Parker, Behrouz Minaei-Bidgoli, Guy Albertelli II, Wolfgang Bauer, and Edwin Kashy, Effective Feedback to the Instructor from Online Homework, Journal of Asynchronous Learning Networks 9(2), 19 — 28 (2005)
  8. Gerd Kortemeyer, Wolfgang Bauer, Walter Benenson, and Edwin Kashy, Retaking a Test Online, The Physics Teacher 44(4), 235 — 239 (2006)
    Tests and midterms given during the running semester are, in the mindset of most educators, located somewhere between formative and summative assessment: more serious than homework, but still - as opposed to the final exam - mostly a learning opportunity. In the mindset of most learners, however, these venues are purely summative - they "flunked" or "did well" on a test, but mostly, they got it over with. Few students come to office hours to understand what they did wrong. If they had a bad day, they have no second chance to correct their mistakes, but more importantly, they do not receive any immediate incentive or reward to address detected deficiencies, or for deeper learning,reviewing, and understanding of the material after the test is over.
  9. Gerd Kortemeyer, An analysis of asynchronous online homework discussions in introductory physics courses, American Journal of Physics 74(6), 526 — 536 (2006)
    Asynchronous online student discussions of online homework problems in introductory physics courses are analyzed with respect to course type, student course performance, student gender, problem difficulty, and problem type. It is found that these variables can significantly change the character of online student collaborations.
  10. Gerd Kortemeyer, Correlations between student discussion behavior, attitudes, and learning, Phys. Rev. ST Phys. Educ. Res. 3, 010101‐1 — 010101‐8 (2007)
    An important result of physics education research is that students' learning and success in a course is correlated with their beliefs, attitudes, and expectations regarding physics. However, it is hard to assess these beliefs for individual students, and traditional survey instruments such as the Maryland Physics Expectations Survey (MPEX) are intended to evaluate the impact of one or more semesters of instruction on an overall class and improve teaching. In this study, we investigate the possibility of using the analysis of online student discussion behavior as an indicator of an individual student’s approach to physics. These discussions are not tainted by the effects of self-reporting, and are gathered in authentic nonresearch settings, where students attempt to solve problems in the way that they believe is most efficient and appropriate. We calculate the correlation of both MPEX and student discussions with different measures of student learning, and find that on an individual base, student discussions are a stronger predictor of success than MPEX outcomes.
  11. Gerd Kortemeyer, The Challenge of Teaching Introductory Physics to Premedical Students, The Physics Teacher 45(9), 552 — 557 (2007)
    Most physics instructors are motivated by a genuine interest in their subject area and in using physics to understand real-world phenomena. While many premedical students may share these interests, most are motivated by fulfilling their degree requirements and gaining admittance into medical school. To achieve this latter goal, they need excellent grades and have to do well on the Medical College Admissions Test (MCAT), which includes a physical sciences section that may not coincide with the learning goals of many physics courses. Too often both sides simply give up, and courses come to some kind of unspoken agreement of how to go through the motions of completing the course with the least amount of mutual aggravation, while real physics falls by the wayside. But how exactly does this discrepancy manifest itself, and what —if anything other than giving up — can be done about it? In this paper, I first survey learner beliefs, expectations, and preferences and then attempt to identify approaches and resources that may partly address the identified issues.
  12. Gerd Kortemeyer, A Polarizer Demo Using LCDs, The Physics Teacher 46(1), 58 (2008)
  13. Gerd Kortemeyer, Edwin Kashy, Walter Benenson, and Wolfgang Bauer, Experiences using the open-source learning content management and assessment system LON-CAPA in introductory physics courses, American Journal of Physics 76(4&5), 438 — 444 (2008)
    We discuss the development and functionality of the LON-CAPA system with a particular focus on its homework and examination functionality. We also describe its more general approach to course management and its infrastructure for course content sharing and reuse. We then focus on measures of student learning and the effectiveness of different content types.
  14. Peng Han, Gerd Kortemeyer, Bernd J. Krämer, and Christine von Prümmer, Exposure and Support of Latent Social Networks Among Learning Object Repository Users, Journal of Universal Computer Science 14(10), 1717 — 1738 (2008)
    Although immense efforts have been invested in the construction of hundreds of learning object repositories, the degree of reuse of learning resources maintained in such repositories is still disappointingly low. As the reasons for this observation are not well understood, we carried out an empirical investigation with the objectives to identify recurring patterns in the retrieval and (re-) use of learning resources and to design and test social networking functionality supporting communities of practice. The outcomes of this project, which are reported here, aim to affect the design of a new generation of learning object repositories, like CampusContent, that tries to eliminate deficits of current repositories and involve recent contributions in the area of social software. Object of our investigation was LON-CAPA, a crossinstitutional learning content management and assessment system used since 2000. We analyzed hundreds of thousands of log data collected over a period of three years and detected various kinds of latent relationships among LON-CAPA users, such as the co-occurrence of learning resources from independent authors in instructional materials. To understand the rationale behind these findings, we conducted a study with LON-CAPA users. One section of the questionnaire asked for people's opinion about the expected benefit of community support. Nearly 80% of the study participants said that the formation of communities of practice (CoP) would be an asset to LON-CAPA. More than 80% would be ready to provide their profiles for matching up with CoPs and serve the community by spending time on the evaluation of resources they had used. Finally we sketch a faceted search functionality we designed to support CoPs among LON-CAPA users. This functionality is currently tested with two CoPs.
  15. Gerd Kortemeyer, Gender differences in the use of an online homework system in an introductory physics course, Phys. Rev. ST Phys. Educ. Res. 5, 010107‐1 — 010107‐8 (2009)
    The two genders make different use of being allowed multiple tries to solve online homework problems: male students frequently attempt to immediately solve the problem, while female students are more likely to first interact with peers and teaching assistants before entering answers. More male than female students state that they use the multiple allowed attempts to enter “random stuff,” while more female than male students state that the multiple attempts allow them to explore their own problem solving approaches without worrying or being stressed out by grades.
  16. Gerd Kortemeyer and Catherine Westfall, History of Physics: Outing the Hidden Curriculum?, American Journal of Physics 77(10), 875 — 881 (2009)
    We describe a history of physics course, cotaught by a physicist and a historian of physics,on the quantum and relativity revolutions in the early part of the 20th century. The course has been taught both in Europe as part of a study abroad program and as a regular on-campus course, which could serve as a model for implementation elsewhere. We present some evidence that this course format can favorably influence students’ epistemological beliefs and expectations about physics.
  17. Gerd Kortemeyer, Apparatus for Teaching Physics: Experimenting with Constant Current and Voltage Sources,, The Physics Teacher 48(1), 68 — 69 (2010)
    While students might be perfectly able to calculate complex electric circuits using Kirchhoff's laws, they frequently fail to solve apparently much simpler conceptual problems involving circuits with just two or three light bulbs and a battery.1 McDermott and Shaffer found that one of the problems is that students conceptualize the battery as a constant current source rather than a constant voltage source.2 To help students confront this common misconception, we present some experiments and concept questions with an actual constant current source.
  18. Gerd Kortemeyer and Catherine Westfall, The Physical Tourist: A European Study Course, Physics in Perspective 12(1), 89 — 99 (2010)
    We organized and led a European study course for American undergraduate university students to explore the early history of relativity and quantum theory. We were inspired by The Physical Tourist articles published in this journal on Munich, Bern, Berlin, Copenhagen, and Göttingen. We describe this adventure both for others wishing to teach such a course and for anyone wishing to walk in the footsteps of the physicists who revolutionized physics in the early decades of the twentieth century.
  19. Gerd Kortemeyer and Peter Riegler, Large-Scale E-Assessments, Prüfungsvor- und -nachbereitung: Erfahrungen aus den USA und aus Deutschland, Zeitschrift für E-Learning 10(1), 8 — 22 (2010)
    Online-Prüungssysteme können die ganze Kette von Prüfungen, angefangen bei formativen Assessments, über die eigentliche Prüfung bis hin zur Prüfungsnachbereitung, unterstützen. Durch diese Systeme werden Lehrszenarien und Applikationen ermöglicht, die mit traditionellen Methoden häufig nur mit sehr großem Aufwand realisierbar wären. Eine Anpassung an lokale Besonderheiten und Randbedingungen sind in der Regel problemlos möglich, wie wir hier anhand von Erfahrungen aus Deutschland und USA erläutern.
  20. Émerson Cruz, Brian O'Shea, Werner Schaffenberger, Steven F. Wolf, and Gerd Kortemeyer, Tutorials in Introductory Physics: The Pain and the Gain,, The Physics Teacher 48(7), 453 — 457 (2010)
    In an introductory physics sequence with a large enrollment of premedical students, traditional recitation sessions were replaced by Tutorials in Introductory Physics, developed by the Physics Education Group at the University of Washington. Initially, summative test scores (as well as FCI scores) dramatically increased, but so did student complaints and workload. Both effects decreased over time. The paper discusses issues that instructors should consider when contemplating implementation of the tutorials.
  21. Peter Riegler and Gerd Kortemeyer, Praxisbericht: Mehrwert freier elektronischer Übungsaufgaben in MINT-Fächern, Zeitschrift für E-Learning 10(3), 53 — 59 (2010)
    In naturwissenschaftlich-technischen Fächern gibt es inzwischen eine an elektronischen Entwicklungszyklen gemessene lange Tradition der freien Bildungsressourcen. Dabei spielen elektronische Übungsmaterialien, insbesondere Aufgaben, eine besondere Rolle. Der Mehrwert für Lehrende besteht neben der kostenfreien Bereitstellung innovativen Lehrmaterials vor allem darin, bekannte Defizite der Lehre in diesen Fächern gezielt anzugehen. Auf der technischen und organisatorischen Seite bedarf die nachhaltige Bereitstellung solcher Lehrressourcen geeigneter Strukturen. Die Struktur und Verwendung von Sammlungen freier Bildungsressourcen wiederum weist Charakteristika auf, die zum Teil aus anderen wissenschaftlichen Kontexten bekannt sind und auch über das Vermitteln naturwissenschaftlich-technischer Inhalte und Konzepte hinaus gültig sein dürften.
  22. Julie Libarkin, Emily Ward, Steven Anderson, Gerd Kortemeyer, and Stuart Raeburn, Revisiting the Geoscience Concept Inventory: A Call to the Community, Geological Society of America Today 21(8), 26 — 28 (2011)
    The use of concept inventories in science and engineering has fundamentally changed the nature of instructional assessment. Nearly a decade ago, we set out to establish a baseline for widespread and integrated assessment of entry-level geoscience courses. The result was the first Geoscience Concept Inventory (GCI v.1.0). We are now retiring GCI v.1.0 and rebuilding the GCI as a more community-based, comprehensive, and effective instrument. We are doing this in the hopes that GCI users, many of whom have expressed a need for a revised and expanded instrument, and the geoscience community at large will view it as a springboard for collaborative action and engagement. If we work together as collaborators, the geosciences have the potential to evaluate learning across our community and over time.
  23. Émerson Cruz, Hélio Dias, and Gerd Kortemeyer, The effect of formative assessment in Brazilian university physics courses, Revista Brasileira de Ensino de Física 33(4), 4315 — 4315 (2011)
    Most postsecondary physics courses in Brazil offer no meaningful formative assessment opportunities. We implemented online homework with immediate feedback in two courses, one with traditional learners at a public university, and one with non-traditional learners at a private university. In addition, at the public university, clickers were used in lecture. While surveys showed broad acceptance of these techniques by the students and the belief that they helped in learning, grades did not significantly improve - instead, we observed a narrowing of the grade distribution toward mid-range grades at the public university, and no difference at the private university. Our study also identifies a number of logistical and organizational hurdles that need to be overcome before a hopefully more successful implementation of these techniques should be attempted.
  24. Steven F. Wolf, Daniel P. Dougherty, and Gerd Kortemeyer, Empirical Approach to Interpreting Card-Sorting Data, Phys. Rev. ST Phys. Educ. Res. 8, 010124‐1 — 010124‐15 (2012)
    Since it was first published 30 years ago, the seminal paper of Chi et al. on expert and novice categorization of introductory problems led to a plethora of follow-up studies within and outside of the area of physics. These studies frequently encompass “card-sorting” exercises whereby the participants group problems. While this technique certainly allows insights into problem solving approaches, simple descriptive statistics more often than not fail to find significant differences between experts and novices. In moving beyond descriptive statistics, we describe a novel microscopic approach that takes into account the individual identity of the cards and uses graph theory and models to visualize, analyze, and interpret problem categorization experiments. We apply these methods to an introductory physics (mechanics) problem categorization experiment, and find that most of the variation in sorting outcome is not due to the sorter being an expert versus a novice, but rather due to an independent characteristic that we named “stacker” versus “spreader.” The fact that the expert-novice distinction only accounts for a smaller amount of the variation may explain the frequent null results when conducting these experiments.
  25. James T. Laverty and Gerd Kortemeyer, Function Plot Response: A Scalable System for Teaching Kinematics Graphs, American Journal of Physics 80(8), 724 — 733 (2012)
    Understanding and interpreting graphs are essential skills in all sciences. While students are mostly proficient in plotting given functions and reading values off graphs, they frequently lack the ability to construct and interpret graphs in a meaningful way. Students can use graphs as representations of value pairs, but often fail to interpret them as the representation of functions, and mostly fail to use them as representations of physical reality. Working with graphs in classroom settings has been shown to improve student abilities with graphs, particularly when the students can interact with them. We introduce a novel problem type in an online homework system, which requires students to construct the graphs themselves in free form, and requires no hand-grading by instructors. Initial experiences using the new problem type in an introductory physics course are reported.
  26. Steven F. Wolf, Daniel P. Dougherty, and Gerd Kortemeyer, Rigging the deck: Selecting good problems for expert-novice card-sorting experiments, Phys. Rev. ST Phys. Educ. Res. 8, 020116‐1 — 020116‐7 (2012)
    A seminal study by Chi et al. firmly established the paradigm that novices categorize physics problems by "surface features" (e.g., "incline," "pendulum," "projectile motion," etc.), while experts use "deep structure" (e.g., "energy conservation," "Newton 2," etc.). Yet, efforts to replicate the study frequently fail, since the ability to distinguish experts from novices turns out to be highly sensitive to the problem set being used. Exactly what properties of problems are most important in problem sets that discriminate experts from novices in a measurable way? To answer this question, we studied the categorizations by known physics experts and novices using a large, diverse set of problems. This set needed to be large so that we could determine how well experts and novices could be discriminated by considering both small subsets using an exhaustive Monte Carlo approach and larger subsets using simulated annealing. We found that the number of questions required to accurately classify experts and novices can be surprisingly small so long as the problem set is carefully crafted to be composed of problems with particular pedagogical and contextual features. Finally, we found that not only was what you ask (deep structure) important, but also how you ask it (problem context).
  27. James T. Laverty, Wolfgang Bauer, Gerd Kortemeyer, and Gary Westfall, Want to Reduce Guessing and Cheating While Making Students Happier? Give More Exams!, The Physics Teacher 50(9), 540 — 543 (2012)
    It is almost universally agreed that more frequent formative assessment (homework, clicker questions, practice tests, etc.) leads to better student performance and generally better course evaluations.1 There is, however, only anecdotal evidence that the same would be true for more frequent summative assessment (exams). There maybe many arguments against giving more exams, including the general “pain” associated with examinations, as well as reduced teaching time, since classroom sessions are dedicated to exams rather than lecturing. We present evidence that increasing the number of exams in fact does lead to better learning success, less cheating and guessing on homework, and better student course evaluations.
  28. Gerd Kortemeyer, Jordan Fish, Jesse Hacker, Justin Kienle, Alexander Kobylarek, Michael Sigler, Bert Wierenga, Ryan Cheu, Ebae Kim, Zachary W. Sherin, Sonny Sidhu, and Philip Tan, Seeing and Experiencing Relativity - A New Tool for Teaching?, The Physics Teacher 51(8), 460 — 461 (2013)
    "What would you see if you were riding a beam of light?" This thought experiment, which Einstein reports to have "conducted" at the age of 16, of course has no sensible answer: as Einstein published a decade later, you could never reach the speed of light. But it does make sense to ask what you would see if you were traveling close to the speed of light, and one of the first physicists to embark on this effort was George Gamow in his Mr. Tompkins in Wonderland. His protagonist is speeding on a bicycle through a city where the speed of light is lower, thus ingeniously taking advantage of the fact that special relativity scales with v/c: for it to kick in, you either have to move very fast (in rather unfamiliar territory), or light has to be slow (in which case special relativity kicks in at everyday velocities in everyday situations). Gamow provides drawings of what Mr. Tompkins and people at the curb would see in this slow-light city, at least, what they would see if one only took into account two of the effects: length contraction and time dilation.
  29. Stefan Dröschler, Gerd Kortemeyer, and Peter Riegler, Openness: weniger ist mehr?, Zeitschrift für Hochschulentwicklung 8(4), 12 — 25 (2013)
    Open Educational Resources führen im Bereich der regulären Hochschulausbildung ein Schattendasein, welches bei weitem nicht ihrem Potential Genüge tut. Der Artikel bespricht einige mögliche Adoptionshürden und zeigt auf, wie ein modifiziertes Verständnis von "Openness" in Verbindung mit einer dementsprechenden Plattform diese Hürden ausräumen kann. Anhand von Nutzungsdaten aus einem etablierten System wird dargestellt, wie eine solche Architektur zu einem nachhaltigen Geben und Nehmen von Bildungsressourcen unter Lehrenden führen und obendrein innovative Lehrmodelle unterstützen kann.
  30. Gerd Kortemeyer, Stefan Dröschler, and David E. Pritchard, Harvesting Latent and Usage-based Metadata in a Course Management System to Enrich the Underlying Educational Digital Library, International Journal on Digital Libraries 14(1), 1 — 15 (2014)
    In this case study, we demonstrate how in an integrated digital library and course management system, metadata can be generated using a bootstrapping mechanism. The integration encompasses sequencing of content by teachers and deployment of content to learners. We show that taxonomy term assignments and a recommender system can be based almost solely on usage data (especially correlations on what teachers have put in the same course or assignment). In particular, we show that with minimal human intervention, taxonomy terms, quality measures, and an association ruleset can be established for a large pool of fine-granular educational assets.
  31. Gerd Kortemeyer, Extending Item Response Theory to Online Homework, Phys. Rev. ST Phys. Educ. Res. 10, 010118‐1 — 010118‐9 (2014)
    Item response theory (IRT) becomes an increasingly important tool when analyzing “big data” gathered from online educational venues. However, the mechanism was originally developed in traditional exam settings, and several of its assumptions are infringed upon when deployed in the online realm. For a large-enrollment physics course for scientists and engineers, the study compares outcomes from IRT analyses of exam and homework data, and then proceeds to investigate the effects of each confounding factor introduced in the online realm. It is found that IRT yields the correct trends for learner ability and meaningful item parameters, yet overall agreement with exam data is moderate. It is also found that learner ability and item discrimination is robust over a wide range with respect to model assumptions and introduced noise. Item difficulty is also robust, but over a narrower range.
  32. Daniel T. Seaton, Gerd Kortemeyer, Yoav Bergner, Saif Rayyan, and David E. Pritchard, Analyzing the Impact of Course Structure on eText Use in Blended Introductory Physics Courses, American Journal of Physics 82(12), 1186 — 1197 (2014)
    We investigate how elements of course structure (i.e., the frequency of assessments as well as the sequencing and weight of course resources) influence the usage patterns of electronic textbooks (e-texts) in introductory physics courses. Specifically, we analyze the access logs of courses at Michigan State University and the Massachusetts Institute of Technology, each of which deploy e-texts as primary or secondary texts in combination with different formative assessments (e.g., embedded reading questions) and different summative assessment (exam) schedules. As such studies are frequently marred by arguments over what constitutes a "meaningful" interaction with a particular page (usually judged by how long the page remains on the screen), we consider a set of different definitions of "meaningful" interactions. We find that course structure has a strong influence on how much of the e-texts students actually read, and when they do so. In particular, courses that deviate strongly from traditional structures, most notably by more frequent exams, show consistently high usage of the materials with far less "cramming" before exams.
  33. Gerd Kortemeyer, An Empirical Study of the Effect of Granting Multiple Tries for Online Homework, American Journal of Physics 83(7), 646 — 653 (2015)
    When deploying online homework in physics courses, an important consideration is how many tries learners should be allowed to solve numerical free-response problems. While on the one hand, this number should be large enough to allow learners mastery of concepts and avoid copying, on the other hand, granting too many allowed tries encourages counter-productive behavior. We investigate data from an introductory calculus-based physicscourse that allowed different numbers of tries in different semesters. It turns out that the probabilities for successfully completing or abandoning problems during a particular try are independent of the number of tries already made, which indicates that students do not learn from their earlier tries. We also find that the probability for successfully completing a problem during a particular try decreases with the number of allowed tries, likely due to increased carelessness or guessing, while the probability to give up on a problem after a particular try is largely independent of the number of allowed tries. These findings lead to a mathematical model for learner usage of multiple tries, which predicts an optimum number of five allowed tries.
  34. Gerd Kortemeyer, The Google calculator, The Physics Teacher 53, 375 — 376 (2015)
    There is a little gem hidden in Google: the calculator. This gadget is capable of assisting students and teachers in a lot of the otherwise tedious calculations in introductory physics.
  35. Gerd Kortemeyer, The Losing Battle against Plug-and-Chug, The Physics Teacher 54, 14 — 17 (2016)
    I think most physics teachers would agree that two important components of a proper solution to a numerical physics problem are to first figure out a final symbolic solution and to only plug in numbers in the end. However, in spite of our best efforts, this is not what the majority of students is actually doing. Instead, they tend to plug numbers into formulas without considering the physical meaning of the equations, then frequently take the result and plug it into the next formula — a strategy known as "plug-and-chug." In this chain of calculations, frequently physical insights are lost. If teaching problem solving is proving ineffective, maybe it is possible to steer students onto the right path by posing the problems in different ways?
  36. Zachary W. Sherin, Ryan Cheu, Philip Tan, and Gerd Kortemeyer, Visualizing Relativity: the OpenRelativity Project, American Journal of Physics 84, 369 — 374 (2016)
    We present OpenRelativity, an open-source toolkit to simulate effects of special relativity within the popular Unity game engine. Intended for game developers, educators, and anyone interested in physics, OpenRelativity can help people create, test, and share experiments to explore the effects of special relativity. We describe the underlying physics and some of the implementation details of this toolset with the hope that engaging games and interactive relativistic "laboratory" experiments might be implemented.
  37. Gerd Kortemeyer, The Psychometric Properties of Classroom Response Systems, Journal of Science Education and Technology 25(4), 561 — 574 (2016)
    Classroom response systems (often referred to as "clickers") have slowly gained adoption over the recent decade; however, critics frequently doubt their pedagogical value starting with the validity of the gathered responses: There is concern that students simply "click" random answers. This case study looks at different measures of response reliability, starting from a global look at correlations between formative clicker responses and summative examination performance to how clicker questions are used in context. It was found that clicker performance is a moderate indicator of course performance as a whole, and that while the psychometric properties of clicker items are more erratic than those of examination data, they still have acceptable internal consistency and include items with high discrimination. It was also found that clicker responses and item properties do provide highly meaningful feedback within a lecture context, i.e., when their position and function within lecture sessions are taken into consideration. Within this framework, conceptual questions provide measurably more meaningful feedback than items that require calculations.
  38. Gerd Kortemeyer, Scalable Continual Quality Control of Formative Assessment Items in an Educational Digital Library, International Journal on Digital Libraries 17(2), 143 — 155 (2016)
    An essential component of any library of online learning objects is assessment items, for example, homework, quizzes, and self-study questions. As opposed to exams, these items are formative in nature, as they help the learner to assess his or her own progress through the material. When it comes to quality control of these items, their formative nature poses additional challenges. e.g., there is no particular time interval in which learners interact with these items, learners come to these items with very different levels of preparation and seriousness, guessing generates noise in the data, and the numbers of items and learners can be several orders of magnitude larger than in summative settings. This empirical study aims to find a highly scalable mechanism for continual quality control of this class of digital content with a minimalist amount of additional metadata and transactional data, while taking into account also characteristics of the learners. In a subsequent evaluation of the model on a limited set of transactions, we find that taking into account the learner characteristic of ability improves the quality of item metadata, and in a comparison to Item Response Theory (IRT), we find that the developed model in fact performs slightly better in terms of predicting the outcome of formative assessment transactions, while never matching the performance of IRT on predicting the outcome of summative assessment.
  39. Gerd Kortemeyer, Work Habits of Students in Traditional and Online Sections of an Introductory Physics Course, Journal of Science Education and Technology 25(5), 697 — 703 (2016)
    The study compares the work habits of two student groups in an introductory physics course, one in traditional and one in online sections. Both groups shared the same online materials and online homework, as well as the same discussion boards and examinations, but one group in addition had traditional lectures. The groups were compared with respect to amount and frequency of access to different online course resources. It was found that with few exceptions, both groups exhibited very similar work habits. Students in the online sections more frequently accessed content pages and more frequently contributed to course discussions. It was also found that regular access of the materials throughout the week, rather than only on homework deadline nights, is a predictor of success on examinations, and that this indicator is more reliable for students in the online sections. Overall, though, the effect of traditional lectures is minimal.
  40. Peter Riegler, Andreas Simon, Marcus Prochaska, Christian Kautz, Rebekka Bierwirth, Susan Hagendorf, and Gerd Kortemeyer, Using Tutorials in Introductory Physics on Circuits in a German University Course: Observations and Experiences, Physics Education 51(6), 065014‐1 — 065014‐15 (2016)
    We describe the implementation of Tutorials in Introductory Physics in a German university course. In particular, we investigate if the conceptual challenges that gave rise to the development of Tutorials are also found among German students, which hurdles to the implementation of Tutorialsare encountered in a German context, and how Tutorials are perceived in this different context. To that end, video recordings from workgroup sessions and guided group discussions with students and teaching assistants, as well as interviews with faculty are analysed. It was found that German students enter introductory physics courses with a different set of prior knowledge than their US-American counterparts, which together with implementation hurdles and negative perceptions by students, teaching assistants, and faculty led to the discontinuation of Tutorials after only one semester.
  41. Emre Gönülateş and Gerd Kortemeyer, Modeling Unproductive Behavior in Online Homework in Terms of Latent Student Traits: An Approach Based on Item Response Theory, Journal of Science Education and Technology 26(2), 139 — 150 (2017)
    Homework is an important component of most physics courses. One of the functions it serves is to provide meaningful formative assessment in preparation for examinations. However, correlations between homework and examination scores tend to be low, likely due to unproductive student behavior such as copying and random guessing of answers. In this study, we attempt to model these two counterproductive learner behaviors within the framework of Item Response Theory in order to provide an ability measurement that strongly correlates with examination scores. We find that introducing additional item parameters leads to worse predictions of examination grades, while introducing additional learner traits is a more promising approach.
  42. Zachary W. Sherin, Philip Tan, Heather Fairweather, and Gerd Kortemeyer, "Einstein's Playground": An Interactive Planetarium Show on Special Relativity, The Physics Teacher 55, 550 — 554 (2017)
    The understanding of many aspects of astronomy is closely linked with relativity and the finite speed of light, yet relativity is generally not discussed in great detail during planetarium shows for the general public. One reason may be the difficulty to visualize these phenomena in a way that is appropriate for planetariums; another may be their distance from everyday experiences that makes it hard for audiences to connect with the presentation. In this paper, we describe an effort to visualize special relativity phenomena in an immersive "everyday" scenario. In order to bring special relativity to human scale, we simulate a universe in which the speed of light is slower, so that "everyday" speeds become relativistic. We describe the physics and the technical details of our first planetarium show, "Einstein's Playground," which premiered at the Museum of Science, Boston.
  43. DeVaughn Croxton and Gerd Kortemeyer, Informal physics learning from video games: a case study using gameplay videos, Physics Education 53(1), 015012‐1 — 015012‐12 (2018)
    Researching informal gameplay can be challenging, since as soon as a formal study design is imposed, it becomes neither casual nor self-motivated. As a case study of a non-invasive design, we analyze publicly posted gameplay videos to assess the effectiveness of a physics educational video game on special relativity. These videos offer unique insights into informal learning through gaming, as players do not only describe the gameplay mechanics, but also explore physics concepts in a think-aloud fashion while they ponder the experience and effects. We find that while this methodology has substantial limitations, it is complementary when it comes to assessing motivations and attitudes, as well as to gathering data on conceptual hurdles.
  44. Gerd Kortemeyer and Anna F. Kortemeyer, The Nature of Collaborations on Programming Assignments in Introductory Physics Courses: A Case Study, European Journal of Physics 39(5), 055705‐1 — 055705‐20 (2018)
    We are providing a mixed-method case study of student collaborations on a programming assignment in an introductory physics course for non-majors. Clustering techniques provide insights on code similarity, and network analysis uncovers social networking in the completion of the assignment. These results are complemented by an open-ended survey, which aims to explain the formation of these network structures, as well as elicit affective and epistemological feedback. It was found that students generally underestimate the size of their collaboration network, except for students who feel overwhelmed by the task — these students believe that everybody copies. The crucial question whether student learning is aided or hindered by these collaborations leads to recommendations for future implementations of programming activities and assignments in physics courses.
  45. Gerd Kortemeyer, Daniel Anderson, Ann Marie Desrochers, Amanda Hackbardt, Kelsie Hoekstra, Alexander Holt, Asif Iftekhar, Tyler Kabaker, Nicole Keller, Zosha Korzecke, Angelos Gogonis, Quincy Manson, George McNeill, Dev Mookerjee, Sean Nguyen, Benjamin Person, Madeline Stafford, Lucas Takamoribraganca, Zeren Yu, Fanjun Zeng, and Rabindra Ratan, Using a Computer Game to Teach Circuit Concepts, European Journal of Physics 40(5), 055703‐1 — 055703‐10 (2019)
    We describe the development and use of Kirchhoff's Revenge, a freely available computer game designed to teach circuit laws in introductory physics courses at the high-school and undergraduate level. In this case study, we describe design principles, effort involved in developing the game, as well as player experiences and feedback. We also report on concept-test results for time-independent scenarios (batteries, wires, and lightbulbs), where we find that conceptual learning gains from playing the game alone are similar to those from traditional instruction alone, but inferior to a combination of traditional instruction with investigative, physical laboratory experiments.
  46. Gerd Kortemeyer, Quick-and-Dirty Item Response Theory, The Physics Teacher 57, 608 — 610 (2019)
    Item Response Theory (IRT) has proven useful in physics education research to examine the validity of concept tests and online homework, yet as a tool for the improvement of physics instruction (particularly exams), it is oftentimes perceived as a) mysterious, b) unjustified, and c) impractical. This article aims to debunk some of those prejudices and provide a quick-and-dirty guide; it does not do any justice to the associated psychometric theories.
  47. Menny Aka, Meike Akveld, Alexander Caspar, Gerd Kortemeyer, and Marinka Valkering-Sijsling, In-Class Formative Assessment in an Introductory Calculus Class, E-learning and Education (eleed) 13 (2020)
    We report on the usage of an audience response system ("clickers") in an introductory math course, both in terms of practical usage and in terms of answer distributions, test-theoretical properties and clustering of questions. We give examples of the questions ("items") that we used and their associated properties. We found the system to deliver meaningful and reliable results regarding the conceptual learning of the students, and we found these benefits to be robust independent of the particulars of the instructional setting. Finally we found that peer instruction can make clicker usage even more meaningful, as the discrimination of questions increases after discussions between learners.

Conference Proceedings

  1. Gerd Kortemeyer and Wolfgang Bauer, Multimedia Collaborative Content Creation, Proceedings of IEEE Frontiers in Education, Tempe, AZ (1998)
  2. Gerd Kortemeyer, Wolfgang Bauer, Deborah A. Kashy, Edwin Kashy, and Cheryl Speier, The LearningOnline Network with CAPA Initiative, Proceedings of IEEE Frontiers in Education, Reno, NV (2001)
  3. Guy Albertelli II, Behrouz Minaei-Bidgoli, William F. Punch, Gerd Kortemeyer, and Edwin Kashy, Concept Feedback in Computer-Graded Assignments, Proceedings of IEEE Frontiers in Education, Boston, MA (2002)
  4. Behrouz Minaei-Bidgoli, Deborah A. Kashy, Gerd Kortemeyer, and William F. Punch, Predicting Student Performance: An Application of Data Mining Methods with the Educational Web-Based System LON-CAPA, Proceedings of IEEE Frontiers in Education, Boulder, CA (2003)
  5. Gerd Kortemeyer, Guy Albertelli II, Wolfgang Bauer, Felicia Berryman, Jeremy Bowers, Matthew Hall, Edwin Kashy, Deborah A. Kashy, Helen Keefe, Behrouz Minaei-Bidgoli, William F. Punch, Alexander Sakharuk, and Cheryl Speier, The LearningOnline Network with Computer-Assisted Personalized Approach, Proceedings of Computer Based Learning in Science, Nicosia, Cyprus (2003)
  6. Guy Albertelli II, Gerd Kortemeyer, Alexander Sakharuk, and Edwin Kashy, Personalized Examinations in Large On-Campus Classes, Proceedings of IEEE Frontiers in Education (2003)
  7. Behrouz Minaei-Bidgoli, Gerd Kortemeyer, and William F. Punch, Mining Feature Importance: Applying Evolutionary Algorithms within a Web-Based Educational System, Proceedings of International Conference on Cybernetics and Information Technologies, Systems and Applications (2004)
  8. Behrouz Minaei-Bidgoli, Gerd Kortemeyer, and William F. Punch, Optimizing Classification Ensembles via a Genetic Algorithm for a Web-based Educational System, Proceedings of Joint International Association for Pattern Recognition, Lisbon, Portugal (2004)
  9. Behrouz Minaei-Bidgoli, Gerd Kortemeyer, and William F. Punch, Association analysis for an online education system, Proceedings of IEEE International Conference on Information Reuse and Integration, 504 — 509 (2004)
  10. Behrouz Minaei-Bidgoli, Gerd Kortemeyer, and William F. Punch, Enhancing Online Learning Performance: An Application of Data Mining Methods, Proceedings of IASTED International Conference on Computers and Advanced Technology in Education, Kauai, HI 7 (2004)
  11. Matthew Hall, Joyce Parker, Behrouz Minaei-Bidgoli, Guy Albertelli II, Gerd Kortemeyer, and Edwin Kashy, Gathering and Timely Use of Feedback from Individualized On-Line Work, Proceedings of IEEE Frontiers in Education, Savannah, GA (2004)
  12. Guy Albertelli II, Matthew Hall, Gerd Kortemeyer, and Edwin Kashy, Technology in the Teaching and Assessment of Engineering Prerequisite Courses , Proceedings of IEEE Frontiers in Education, Savannah, GA (2004)
  13. Mark Urban-Lurain, Guy Albertelli II, and Gerd Kortemeyer, Using Information Technology to Author, Administer, and Evaluate Performance-Based Assessments, Proceedings of IEEE Frontiers in Education, Indianapolis, IN (2005)
  14. Wolfgang Bauer and Gerd Kortemeyer, Research on Learning in LON-CAPA: Multiple Content Representations, Test Data Banks, Proceedings of Computer Based Learning in Science, Zilina. Slowakia (2005)
  15. Gerd Kortemeyer and Wolfgang Bauer, LON-CAPA, an Open-Source Freeware Learning Content Management and Course Management System, Proceedings of Computer Based Learning in Science, Zilina. Slowakia (2005)
  16. Stuart Raeburn, Edwin Kashy, David Gift, Byron Brown, and Gerd Kortemeyer, Are Two Course Management Systems better than One?, Proceedings of IEEE Frontiers in Education, San Diego, CA (2006)
  17. Gerd Kortemeyer, LON-CAPA – An Open-Source Learning Content Management and Assessment System for the Sciences, Proceedings of m-ICTE Conference, Lisbon, Portugal 1, 407 — 411 (2009)
  18. Gerd Kortemeyer, LON-CAPA – An Open-Source Learning Content Management and Assessment System, Proceedings of EdMedia, Honolulu, HI, 1515 — 1520 (2009)
  19. Gerd Kortemeyer and Émerson Cruz, An Open-Source Learning Content Management and Assessment System, Proceedings of World Conference on Computers in Education, Bento Gonçalves, Brazil 42, 340 — 348 (2009)
  20. Peter Riegler and Gerd Kortemeyer, Gender Differences in Computer Aided Assessments, Workshop Mathematics for Engineers, Wismarer Frege Reihe 3, 23 — 28 (2010)
  21. Yoav Bergner, Stefan Dröschler, Gerd Kortemeyer, Saif Rayyan, Daniel T. Seaton, and David E. Pritchard, Model-Based Collaborative Filtering Analysis of Student Response Data: Machine-Learning Item Response Theory, Proceedings of International Conference on Educational Data Mining 5, 95 — 102 (2012)
  22. Steven F. Wolf, Daniel P. Dougherty, and Gerd Kortemeyer, Rigging the Deck - Selecting Good Problems for Expert-Novice Card-Sorting Experiments, Physics Education Research Conference, Philadelphia, PA, AIP Conf. Proc. 1513, 426 — 429 (2012)
  23. Gerd Kortemeyer, Philip Tan, and Steven Schirra, A Slower Speed of Light: Developing Intuition about Special Relativity with Games, Proceedings of Foundations of Digital Games, Chania, Crete, Greece (2013)
  24. Daniel T. Seaton, Yoav Bergner, Gerd Kortemeyer, Saif Rayyan, Isaac Chuang, and David E. Pritchard, The Impact of Course Structure on eText Use in Large-Lecture Introductory-Physics Courses, Physics Education Research Conference, Portland, OR, AIP Conf. Proc. (2013)
  25. Gerd Kortemeyer, Lessons from (almost) 25 years of hybrid and online physics courses at Michigan State University., Proceedings of EdMedia, Washington, DC, 148 — 152 (2017)
  26. Gerd Kortemeyer, Game Development for Teaching Physics, GIREP, Dublin, Ireland, J. Phys.: Conf. Ser. 1286, 012048‐1 — 012048‐7 (2019)
  27. Gerd Kortemeyer, Gamification of Circuit Laws - Kirchhoff's Revenge, Proceedings of EdMedia, Amsterdam, Netherlands, 1170 — 1176 (2018)
  28. Gerd Kortemeyer, It's all in the data - but what is it? Learning analytics and data mining of multimedia physics courses, World Conference on Physics Education, Sao Paulo, Brazil, International Journal of Physics and Chemistry Education 11(1), 13 — 17 (2019)
  29. Gerd Kortemeyer and Stefan Dröschler, Support Effective Formative Assessment Through Collaborative Filtering: A Case Study, Proceedings of EdMedia, Amsterdam, Netherlands, 1259 — 1271 (2019)
  30. Gerd Kortemeyer, Incorporating Computational Exercises into Introductory Physics Courses, International Conference on Physics Education, Johannesburg, South Africa, J. Phys.: Conf. Ser. 1512, 012025‐1 — 012025‐8 (2020)
  31. Gerd Kortemeyer, Game Development for Teaching Physics, International Conference on Physics Education, Johannesburg, South Africa, J. Phys.: Conf. Ser. 1512, 012024‐1 — 012024‐8 (2020)

Books

  1. Gerd Kortemeyer et al., Coprozessoren Programmierung mit Turbo Pascal und C++, IWT Verlag (International Thompson Publishing) (Vaterstetten, Germany), ISBN: 3-88322-439-1 (1993)

Book Chapters

  1. Behrouz Minaei-Bidgoli, Pang-Ning Tan, Gerd Kortemeyer, and William F. Punch, Association analysis for a web-based educational system, in C. Romero and S. Ventura (Eds.), Data-Mining in E-Learning, WITpress (Southampton, Boston), ISBN: 1-84564-152-3 (2006)
  2. Susanne Bellmer, Gerd Kortemeyer, and Peter Riegler, Computerbewertete Übungen in mathematischen, technischen und naturwissenschaftlichen Grundlagenfächern, in Hans-Jürgen Appelrath and Leonore Schulze (Eds.), Auf dem Weg zu exzellentem E-Learning - Kooperation und Vernetzung der Hochschullehre in Niedersachsen, Waxmann Verlag (Münster, New York, München, Berlin), ISBN: 978-3-8309-2122-6 (2009)

Other Publications

  1. Gerd Kortemeyer, 80387 aktiviert, c't 4, 260 (1992)
  2. Gerd Kortemeyer, APS-Zeitschriften wachsen exponentiell, Physikalische Blätter 3, 198 (1996)
  3. Gerd Kortemeyer (script and video material compilation), Energy Innovation (video), Cable News Network (CNN), Atlanta, GA (1996)
  4. Gerd Kortemeyer (script and video material compilation), Nuclear Stockpile Reliability (video), Cable News Network (CNN), Atlanta, GA (1996)
  5. Gerd Kortemeyer (script and video material compilation), Nuclear Stockpile Security (video), Cable News Network (CNN), Atlanta, GA (1996)
  6. Gerd Kortemeyer (background research and video material compilation), Feynman lives! (video), Cable News Network (CNN), Atlanta, GA (1996)
  7. Gerd Kortemeyer (translator), Introductory Physics - German Version (cliXX Physik) (CD-ROM), Verlag Harri Deutsch, Germany, ISBN: 3-8171-1593-8 (1998)
  8. Cheryl Speier and Gerd Kortemeyer, Open Source Objects for Teaching and Learning, Syllabus Magazine 11 (2001)
  9. Gerd Kortemeyer, The Evolving Growth of LON-CAPA, Campus Technology, 3 (2006)
  10. Gerd Kortemeyer, Fertiggerichte aus der Tiefkühltruhe (Interview), CampusInnovation (2007)
  11. Gerd Kortemeyer (contributor), End-of-Chapter homework problems, in Raymond A. Serway, Chris Vuille, and Jerry S. Faughn (Eds.), College Physics, Cengage, ISBN: 0-49538-693-6 (2008)
  12. Susanne Bellmer, Peter Riegler, Gerd Kortemeyer, and Gerd von Cölln, Projektbericht: VITA - Virtual Teaching Assistant, E-learning and Education (eleed), 5 (2009)
  13. Gerd Kortemeyer and Peter Riegler, Automatisch bewertete Übungsaufgaben und Übungsmaterialien, Die Neue Hochschule 50(2), 34 — 37 (2009)
  14. Emily Ward, Julie Libarkin, Stuart Raeburn, and Gerd Kortemeyer, The Geoscience Concept Inventory WebCenter provides new means for student assessment, eLearning Papers, 20 (2010)
  15. Peter Riegler and Gerd Kortemeyer, LON-CAPA - eAsssessment im internationalen Verbund, Hamburger eLearning Magazin 7, 53 — 55 (2011)
  16. Gerd Kortemeyer (product owner), Philip Tan, Ryan Cheu, Ebae Kim, Zachary W. Sherin, Sonny Sidhu (producer), and Abe Stein, A Slower Speed of Light (video game), MIT Game Lab (2012)
  17. Gerd Kortemeyer, Ten Years Later: Why Open Educational Resources Have Not Noticeably Affected Higher Education, and Why We Should Care, EDUCAUSE Review Online (2013)
  18. Gerd Kortemeyer, Open Educational Resources (OERs) - Eine gescheiterte Revolution, eduKnow edu-sharing Wissenssammlung (2013)
  19. Gerd Kortemeyer, 15 years of online physics courses at Michigan State University, American Physical Society Forum on Education (FED) Newsletter (2014)
  20. Gerd Kortemeyer, Digital Rights Management: The Bane of Electronic Texts, EDUCAUSE Review Online (2014)
  21. Gerd Kortemeyer, Over two decades of blended and online physics courses at Michigan State University, E-learning and Education (eleed), 10 (2014)
  22. Gerd Kortemeyer, The Two Worlds of Learning Analytics, EDUCAUSE Review Online, 7 (2016)
  23. Gerd Kortemeyer, Researching Online Learning (Interview), Research in Action Podcast [Kathryn Linder], Oregon State University (2017)
  24. Gerd Kortemeyer, The Spectrum of Learning Analytics, E-learning and Education (eleed), 12 (2017)
  25. Zachary W. Sherin, Philip Tan, Heather Fairweather, and Gerd Kortemeyer, Visual Physics: Doppler Rainbows, The Physics Teacher 55, 592 (2017)
  26. Gerd Kortemeyer et al., Kirchhoff's Revenge (video game), Steam (2018)
  27. Gerd Kortemeyer, Physics Education Research: a replicable model for Discipline-Based Educational Research at European universities?, ETH Teaching and Learning Journal 1(2), 137 — 146 (2020)
  28. Gerd Kortemeyer, That's one giant step for a university, one small leap for digitization, Bulletin VSH-AEU 2020(3‐4), 33 — 38 (2020)

Patents

  1. Gerd Kortemeyer and Wolfgang Bauer, System and method for preparing educational materials, US Patent, 8,504,482 (issued August 2013)
  2. Gerd Kortemeyer and Wolfgang Bauer, System and method to facilitate creation of educational information, US Patent, 8,831,997 (issued September 2014)
  3. Gerd Kortemeyer and Wolfgang Bauer, System and method for preparing and delivering informational content, US Patent, 9,424,565 (issued August 2016)