Current research suggests that by actively involving students, you can increase pedagogical value of algorithm visualizations. We believe that a pedagogically successful visualization, besides actively engaging participants, also requires certain other key features. We compared several existing algorithm visualizations for the purpose of identifying features that we believe increase the pedagogical value of an algorithm visualization. To identify the most important features from this list, we conducted two experiments using a variety of the heapsort algorithm visualizations. The results of these experiments indicate that the single most important feature is the ability to control the pace of the visualization. Providing a good data set that covers all the special cases is important to help students comprehend an unfamiliar algorithm. An algorithm visualization having minimum features that focuses on the logical steps of an algorithm is sufficient for procedural understanding of the algorithm. To have better conceptual understanding, additional features (like an activity guide that makes students cover the algorithm in detail and analyze what they are doing, and pseudocode display of an algorithm) may prove to be helpful, but that is a much harder effect to detect. / Master of Science

OpenDSA is a collection of open source tutorials for teaching data structures and algorithms. It was created with the goals of visualizing complex, abstract topics; increasing the amount of practice material available to students; and providing immediate feedback and incremental assessment. In this thesis, I first describe aspects of the OpenDSA architecture relevant to collecting user interaction data. I then present an analysis of the interaction log data gathered from three classes during Spring 2013. The analysis focuses on determining the time distribution of student activity, determining the time required for assignment completion, and exploring \credit-seeking" behaviors and behavior related to non-required exercises. We identified clusters of students based on when they completed exercises, verified the reliability of estimated time requirements for exercises, provided evidence that a majority of students do not read the text, discovered a measurement that could be used to identify exercises that require additional development, and found evidence that students complete exercises after obtaining credit. Furthermore, we determined that slideshow usage was fairly high (even when credit was not ordered), and skipping to the end of slideshows was more common when credit was offered but also occurred when it was not. / Master of Science

Algorithm visualizations (AVs) have become a popular teaching aid in classes on algorithms and data structures. The AlgoViz Project attempts to provide an online venue for educators, students, developers,researchers, and other AV users. The Project is comprised of two websites. The first, the AlgoViz Portal, provides two major informational resources: an AV catalog that provides both descriptive and evaluative metadata of indexed visualizations, and an annotated bibliography of research literature. Both resources have over 500 entries and are actively updated by the AV community. The Portal also provides field reports, discussion forums, and other community-building mechanisms. The second website, OpenAlgoViz, is a SourceForge site intended to showcase exemplary AVs, as well as provide logistical and hosting support to AV developers. / Master of Science

Algorithm has always been a challenging topic for students to learn because of its high level of abstraction. To provide visual aid for algorithm education, many algorithm visualization systems have been designed, developed, and evaluated for the last two decades. However, neither the topics covered nor the interactivity of most AV systems are satisfying. This problem is presented in detail in chapter 2. As a result, this research aims to design, implement and evaluate a compiler-based algorithm visualization system on complex graph algorithm implementation with the assumption that it can help students build both confidence and competence in understanding it. This system is designed and developed according to the method in chapter 3. To test the hypothesis, a comparison experiment on 10 students in the Computer Graphics Technology department is conducted. The complete test protocol can be found in chapter 3.4, and the result can be found in chapter 4. Based on the limited number of subjects’ testing data, a rough conclusion is made that this AV system has only a slight positive effect on subjects’ confidence and competence in understanding complex graph algorithm’s implementation, and its usability is acceptable. However, a concrete conclusion can only be reached if the testing is conducted to a larger group of subjects. In addition to the objective testing data, some interesting subjective observations, which are listed in chapter 5.2 are also made while doing the test. These observations indicate that algorithm visualization may more of a tool to examine users’understanding of the implementation than a tool to help them learn it.

A Theory of Algorithms course is essential to any Computer Science curriculum at both the undergraduate and graduate levels. It is also considered to be difficult material to teach or to learn. In particular the topics of Computational Complexity Theory, reductions, and the NP-Complete class of problems are considered difficult by students. Numerous algorithm visualizations (AVs) have been developed over the years to portray the dynamic nature of known algorithms commonly taught in undergraduate classes. However, to the best of our knowledge, the instructional material available for NP-Completeness is mostly static and textual, which does little to alleviate the complexity of the topic. Our aim is to improve the pedagogy of NP-Completeness by providing intuitive, interactive, and easy-to-understand visualizations for standard NP Complete problems, reductions, and proofs. In this thesis, we present a set of visualizations that we developed using the OpenDSA framework for certain NP-Complete problems. Our paradigm is a three step process. We first use an AV to illustrate a particular NP-Complete problem. Then we present an exercise to provide a first-hand experience with attempting to solve a problem instance. Finally, we present a visualization of a reduction as a part of the proof for NP-Completeness. Our work has been delivered as a collection of modules in OpenDSA, an interactive eTextbook system developed at Virginia Tech. The tutorial has been introduced as a teaching supplement in both a senior undergraduate and a graduate class. We present an analysis of the system use based on records of online interactions by students who used the tutorial. We also present results from a survey of the students. / Master of Science

Learning technologies in computer science education have been most closely associated with teaching of programming, including automatic assessment of programming exercises. However, when it comes to teaching computer science content and concepts, learning technologies have not been heavily used. Perhaps the best known application today is Algorithm Visualization (AV), of which there are hundreds of examples. AVs tend to focus on presenting the procedural aspects of how a given algorithm works, rather than more conceptual content. There are also new electronic textbooks (eTextbooks) that incorporate the ability to edit and execute program examples. For many traditional courses, a longstanding problem is lack of sufficient practice exercises with feedback to the student. Automated assessment provides a way to increase the number of exercises on which students can receive feedback. Interactive eTextbooks have the potential to make it easy for instructors to introduce both visualizations and practice exercises into their courses. OpenDSA is an interactive eTextbook for data structures and algorithms (DSA) courses. It integrates tutorial content with AVs and automatically assessed interactive exercises. Since Spring 2013, OpenDSA has been regularly used to teach a fundamental data structures and algorithms course (CS2), and also a more advanced data structures, algorithms, and analysis course (CS3) at various institutions of higher education. In this thesis, I report on findings from early adoption of the OpenDSA system. I describe how OpenDSA's design addresses obstacles in the use of AV systems. I identify a wide variety of use for OpenDSA in the classroom. I found that instructors used OpenDSA exercises as graded assignments in all the courses where it was used. Some instructors assigned an OpenDSA assignment before lectures and started spending more time teaching higher-level concepts. OpenDSA also supported implementing a ``flipped classroom'' by some instructors. I found that students are enthusiastic about OpenDSA and voluntarily used the AVs embedded within OpenDSA. Students found OpenDSA beneficial and expressed a preference for a class format that included using OpenDSA as part of the assigned graded work. The relationship between OpenDSA and students' performance was inconclusive, but I found that students with higher grades tend to complete more exercises. / Ph. D.

We report on the state of the field of algorithm visualization, both quantitatively and qualitatively. Computer science educators seem to find algorithm and data structure visualizations attractive for their classrooms. Educational research shows that some are effective while many are not. Clearly, then, visualizations are difficult to create and use right. There is little in the way of a supporting community, and many visualizations are downright poor. Topic distribution is heavily skewed towards simple concepts with advanced topics receiving little to no attention. We have cataloged nearly 400 visualizations available on the Internet. We have a wiki-based catalog which includes availability, platform, strengths and weaknesses, responsible personnel and institutions, and other data about each visualization. We have developed extraction and analysis tools to gather statistics about the corpus of visualizations. Based on analysis of this collection, we point out areas where improvements may be realized and suggest techniques for implementing such improvements. We pay particular attention to the free and open source software movement as a model which the visualization community may do well to emulate, from both a software engineering perspective and a community-building standpoint. / Master of Science

The diploma thesis focuses on software tools which enable algorithm animation. In theoretical section of the work are introduced different ways how to present algorithms. Then the field of algorithm animation is described; it's history, development and current state. In the last part of theoretical section are shown possibilities how to use algorithm animation in teaching. Practical section of the thesis focuses on comparison of selected software tools. Selected tools are evaluated based on several criteria. The applications are then compared by multi-criteria decision making methods. Main goal of this thesis is to compare the selected software tools. Partial goals are to introduce advantages of using such applications compared to writing the algorithm in text form.