Tammy VanDeGrift

Promoting Interaction in Large Classes with Computer-Mediated Feedback

Eliciting student participation in large college classes is difficult yet critical to learning. This paper describes a design experiment with the Classroom Feedback System (CFS), a computer-mediated system for promoting class interaction. We delineate challenges to interaction based on successive background and pilot studies. CFS addresses these challenges by enabling students to post annotations (e. g., More Explanation) directly on lecture slides. The instructor sees the annotations in real time. Evidence from a large lecture study shows that CFS enhances interaction by addressing challenges to interaction.

Videoconferencing and presentation support for synchronous distance learning

Synchronous distance education can partner students and professors from different geographic or cultural regions, allowing them to share and learn from each other. Technology must support the sharing of ideas and materials. Using an iterative design approach, we investigated challenges in synchronous distance learning environments through observation of masters-level courses connecting two learning sites. Through observations, interviews, and surveys we learned of two major challenges: (1) low-quality audio/video makes interaction difficult; and, (2) presentation technologies in distance learning environments make extemporaneous teaching difficult. We developed and deployed a new distance learning system using Internet based video conferencing and a pen computer based presentation system. We studied system use in a masters level course. Analysis of qualitative data (observation notes, surveys, interview transcripts) collected in the course suggest that technological interruptions increased the feeling of separation between the sites, while the integration of natural handwriting with slides increased flexibility and was perceived positively by students and instructors.

Do students recognize ambiguity in software design? a multi-national, multi-institutional report

Successful software engineering requires experience and acknowledgment of complexity, including that which leads designers to recognize ambiguity within the software design description itself. We report on a study of 21 post-secondary institutions from the USA, UK, Sweden, and New Zealand. First competency and graduating students as well as educators were asked to perform a software design task. We found that as students go from first competency to graduating seniors they tend to recognize ambiguities in under-specified problems. Additionally, participants who recognized ambiguity addressed more requirements of the design.

Experience report: getting novice programmers to THINK about improving their software development process

Expertise is developed through both a) self-reflection and b) making useful plans for improvement [3, 10]. Traditional novice-level programming assignments require neither of these skills to be used. Could we get students to think about improving their software development processes? What areas would they identify as needing improvement? Could they write effective plans for themselves? In this experience report, we analyze the results of an intervention with 236 CS1.5 students asking them to do these activities. We find that they most commonly make improvements in planning, compared to coding and testing. Additionally, over half of the plans they make are so vague as to be of little use in helping students identify if they have, in fact, improved. Finally, we asked students at the end of the term to reflect on how their experiences with programming assignments changed over the term. We discuss our results in light of how instructors can focus instruction to help students become more meta-cognitive about their own software development processes.

Commonsense computing (episode 5): algorithm efficiency and balloon testing

This paper investigates what students understand about algorithm efficiency before receiving any formal instruction on the topic. We gave students a challenging search problem and two solutions, then asked them to identify the more efficient solution and to justify their choice. Many students did not use the standard worst-case analysis of algorithms; rather they chose other metrics, including average-case, better for more cases, better in all cases, one algorithm being more correct, and better for real-world scenarios. Students were much more likely to choose the correct algorithm when they were asked to trace the algorithms on specific examples; this was true even if they traced the algorithms incorrectly.

Commonsense understanding of concurrency: computing students and concert tickets

Innate understanding of concurrency helps beginners solve CS problems with multiple processes executing at the same time.

Interaction patterns with a classroom feedback system: making time for feedback

In this paper, we describe two novel patterns of interaction that arose in a study of a computer-mediated feedback system for the university classroom. In both patterns, students gave feedback through the system that they would not have given aloud for lack of an appropriate moment-either because the feedback would be premature or tardy. We describe the patterns themselves and how awareness of the patterns can inform pedagogy and system-building.

Introduction to Special Issue (Part 1): Broadening Participation in Computing Education

This special issue includes the first set of articles addressing broadening participation in computing education. The articles span the stages of the pipeline, from introducing middle school children to computer science to retaining underrepresented groups at the university level. The preface presented here outlines the need for increasing the participation of underrepresented minorities, women, and people with disabilities in the development of technology. In addition, the preface summarizes the six articles included in this first (of two) issues on broadening participation.

Windows scheduling of arbitrary length jobs on parallel machines

The generalized windows scheduling problem for <i>n</i> jobs onmultiple machines is defined as follows: Given is a sequence,<i>I</i> =\ang(<i>w</i>₁,<i>l</i>₁),(<i>w</i>₂, <i>l</i>₂),...,(<i>w</i>_n, <i>l</i>_n) of<i>n</i> pairs of positive integers that are associated with thejobs 1,2,...,<i>n</i>, respectively. The processing length of job<i>i</i> is <i>l</i>_i slots (a slot is the processingtime of one length unit). The goal is to repeatedly andnon-preemptively schedule all the jobs on the fewest possibleparallel machines such that the gap (window) between twoconsecutive executions of the first slot of job <i>i</i> is at most<i>w</i>_i slots. This problem arises in push broadcastsystems in which data is transmitted on parallel channels. The problem is NP-hard even for unit-length jobs and a(1+Σ)-approximation algorithm is known for this case byapproximating the natural lower bound<i>W</i>(<i>I</i>)=Σ₌₁ⁿ(1/<i>W</i>_i). The techniques used for approximatingunit-length jobs cannot be applied for arbitrary-length jobs mainlybecause the optimal number of machines might be arbitrarily largerthan the generalized lower bound<i>W</i>(<i>I</i>)=Σ₌₁ⁿ(<i>l</i>_i/<i>w</i>_i). Our main result is an 8-approximation algorithm for thegeneralized problem using new methods, different from those usedfor the unit-length case. We also present an algorithm that uses2(1+Σ)<i>W</i>(<i>I</i>)+ log <i>w</i>_max machinesand a greedy algorithm that is based on a new tree representationof schedules. The greedy algorithm is optimal for some special andsimulations show that it performs very well in practice.

User interface evaluation by novices

This study examines the extent to which novice computing students with minimal computer science coursework and no training in user interface (UI) evaluation consider UI concepts such as usability, user experience, and the context in which software will be used when evaluating an interface. In analyzing the responses of 149 novice computer science students who were asked to evaluate two interfaces for converting temperatures between Fahrenheit and Celsius, we observed that students generally considered usability and user experience factors, but were less likely to consider context. For educators, this exact task could be given to a class in order to initiate discussion of user-centered design; the study also provides a framework for structuring the discussion. More generally, the results of this study provide insight into some opportunities and challenges in teaching good interface design and evaluation skills.