Doctor of Philosophy

dissertationThis dissertation establishes a new visualization design process model devised to guide visualization designers in building more effective and useful visualization systems and tools. The novelty of this framework includes its flexibility for iteration, actionability for guiding visualization designers with concrete steps, concise yet methodical definitions, and connections to other visualization design models commonly used in the field of data visualization. In summary, the design activity framework breaks down the visualization design process into a series of four design activities: understand, ideate, make, and deploy. For each activity, the framework prescribes a descriptive motivation, list of design methods, and expected visualization artifacts. To elucidate the framework, two case studies for visualization design illustrate these concepts, methods, and artifacts in real-world projects in the field of cybersecurity. For example, these projects employ user-centered design methods, such as personas and data sketches, which emphasize our teams' motivations and visualization artifacts with respect to the design activity framework. These case studies also serve as examples for novice visualization designers, and we hypothesized that the framework could serve as a pedagogical tool for teaching and guiding novices through their own design process to create a visualization tool. To externally evaluate the efficacy of this framework, we created worksheets for each design activity, outlining a series of concrete, tangible steps for novices. In order to validate the design worksheets, we conducted 13 student observations over the course of two months, received 32 online survey responses, and performed a qualitative analysis of 11 in-depth interviews. Students found the worksheets both useful and effective for framing the visualization design process. Next, by applying the design activity framework to technique-driven and evaluation-based research projects, we brainstormed possible extensions to the design model. Lastly, we examined implications of the design activity framework and present future work in this space. The visualization community is challenged to consider how to more effectively describe, capture, and communicate the complex, iterative nature of data visualization design throughout research, design, development, and deployment of visualization systems and tools

Making Data Visualization Design Worksheets Accessible

Accessibility of a document means that the material can be read by a visually impaired person just as well as a person without a visual impairment would. Accessibility is an essential factor of consideration because it allows students with visual impairments and other disabilities to be smoothly integrated into courses. Purdue is making efforts to mandate accessibility within all departments, but there is still a significant gap that needs to be filled. One method of combating a limited document layout, and normalizing accessibility, is to format electronic course documents to be fully compatible with a screen reader. The focus of this research is answering the question, “how can data visualization activity worksheets be designed and made accessible for the visually impaired?” In this study, we will examine scholarly works that provide data visualization worksheets designed to guide novices through the visualization design process. We anticipate design decisions, in previously published works, were made with a focus on the content, not accessibility. In this work, we are developing data visualization activity worksheets to introduce the data visualization process with a focus on accessibility and understanding the intricate stages of the process. The activity worksheets, for this study, are being designed and formatted according to Purdue’s public manual, Accessibility for Instructional Design. Outcomes from this work will support and enable access for all communities and empower all persons to actively engage in the data visualization design process while meeting the requirements for accessibility of electronic information, communication, and technology

Scientific Representational Fluency:Defining, Diagnosing, and Developing

This thesis advocates the importance of representational fluency in physics education. Multiple representations in science (e.g. graphs, words, equations, and diagrams) has been an area of much interest in physics education research in recent years. Representational fluency, however, is a somewhat novel idea. The thesis argues that this little-used term, representational fluency, is a way to draw together various ideas on how and why the use of multiple representations is important for physics students, educators, and education researchers alike. Representational fluency is investigated by considering three questions: what is representational fluency; what role does representational fluency play in physics learning; and how can students’ development of representational fluency be facilitated? This thesis explores these questions through the format of an introduction, five journal articles, and a general discussion combining the conclusions of each paper. The first paper presents the development, use, and publication of a survey to measure representational fluency, the Representational Fluency Survey (RFS), which is the first of such surveys in the literature. The RFS is a seven item survey which involves the participant solving problems that are difficult due to the representations in the question, rather than the level of physics content knowledge. A second paper illustrates how the RFS is used to further develop our understanding of representational fluency. The RFS allowed diagnosis of significant differences in the levels of representational fluency of different cohorts of students at the University of Sydney and identification of various features of students with a high level of representational fluency. It was found that the representational fluency of students with a higher level of physics learning experience was significantly greater than that of students with a lower level of physics learning experience and the difference was evident even within the first year cohort. Due to the apparent disparity of levels of representational fluency amongst different cohorts of students at the university, the subsequent three papers relate to research into effective pedagogies that facilitate the development of representational fluency. A format of presenting direct instruction on a particular physics representation through worksheets and consolidating this knowledge with applied questions was trialled as a possible method of instruction. It was found to alter the way that students use representations in following questions. This was done in the context of students in their final year of high school. The format was adapted to suit a university physics course in the structure of a semester-long set of weekly online learning modules designed to introduce students to representations relevant to the upcoming week’s lectures. The uptake and effectiveness of online learning modules was investigated first: it was found that university students were willing to participate in the modules and that the modules were of benefit to student engagement as intended in their design. Therefore, an experiment was conducted with the first year physics students at the University of Sydney. The students were randomly separated into two streams. One stream participated in weekly online learning modules focussed on relevant physics representations, the other stream participated in similar modules which more conventionally focussed on relevant physics concepts. Using the RFS as a pre-post test, it was found that students participating in the modules on physics representations had the largest learning gains in representational fluency. This demonstrates an effective pedagogical tool to support students in developing their representational fluency. Using an established test of conceptual physics understanding, it was also found that the students from each stream of online learning modules developed conceptual physics knowledge by comparative amounts across the semester. In these ways, this thesis advocates the importance of representational fluency, through defining, diagnosing, and developing representational fluency of university students

Leveraging Peer Feedback to Improve Visualization Education

Peer review is a widely utilized pedagogical feedback mechanism for engaging students, which has been shown to improve educational outcomes. However, we find limited discussion and empirical measurement of peer review in visualization coursework. In addition to engagement, peer review provides direct and diverse feedback and reinforces recently-learned course concepts through critical evaluation of others' work. In this paper, we discuss the construction and application of peer review in a computer science visualization course, including: projects that reuse code and visualizations in a feedback-guided, continual improvement process and a peer review rubric to reinforce key course concepts. To measure the effectiveness of the approach, we evaluate student projects, peer review text, and a post-course questionnaire from 3 semesters of mixed undergraduate and graduate courses. The results indicate that course concepts are reinforced with peer review---82% reported learning more because of peer review, and 75% of students recommended continuing it. Finally, we provide a road-map for adapting peer review to other visualization courses to produce more highly engaged students

Mapping biological ideas: Concept maps as knowledge integration tools for evolution education

Many students leave school with a fragmented understanding of biology that does not allow them to connect their ideas to their everyday lives (Wandersee, 1989; Mintzes, Wandersee, & Novak, 1998; Mintzes, Wandersee, & Novak, 2000a). Understanding evolution ideas is seen as central to building an integrated knowledge of biology (Blackwell, Powell, & Dukes, 2003; Thagard & Findlay, 2010). However, the theory of evolution has been found difficult to understand as it incorporates a wide range of ideas from different areas (Bahar et al., 1999; Tsui & Treagust, 2003) and multiple interacting levels (Wilensky & Resnick, 1999; Duncan & Reiser, 2007; Hmelo-Silver et al., 2007). Research suggests that learners can hold a rich repertoire of co-existing alternative ideas of evolution (for example, Bishop & Anderson, 1990; Demastes, Good, & Peebles, 1996; Evans, 2008), especially of human evolution (for example, Nelson, 1986; Sinatra et al., 2003; Poling & Evans, 2004). Evolution ideas are difficult to understand because they often contradict existing alternative ideas (Mayr, 1982; Wolpert, 1994; Evans, 2008). Research suggests that understanding human evolution is a key to evolution education (for example, Blackwell et al., 2003; Besterman & Baggott la Velle, 2007). This dissertation research investigates how different concept mapping forms embedded in a collaborative technology-enhanced learning environment can support students’ integration of evolution ideas using case studies of human evolution. Knowledge Integration (KI) (Linn et al., 2000; Linn et al., 2004) is used as the operational framework to explore concept maps as knowledge integration tools to elicit, add, critically distinguish, group, connect, and sort out alternative evolution ideas. Concept maps are a form of node-link diagram for organizing and representing connections between ideas as a semantic network (Novak & Gowin, 1984). This dissertation research describes the iterative development of a novel biology-specific form of concept map, called Knowledge Integration Map (KIM), which aims to help learners connect ideas across levels (for example, genotype and phenotype levels) towards an integrated understanding of evolution. Using a design-based research approach (Brown, 1992; Cobb et al., 2003), three iterative studies were implemented in ethnically and economically diverse public high schools classrooms using the web-based inquiry science environment (WISE) (Linn et al., 2003; Linn et al., 2004). Study 1 investigates concept maps as generative assessment tools. Study 1A compares the concept map generation and critique process of biology novices and experts. Findings suggest that concept maps are sensitive to different levels of knowledge integration but require scaffolding and revision. Study 1B investigates the implementation of concept maps as summative assessment tools in a WISE evolution module. Results indicate that concept maps can reveal connections between students’ alternative ideas of evolution. Study 2 introduces KIMs as embedded collaborative learning tools. After generating KIMs, student dyads revise KIMs through two different critique activities (comparison against an expert or peer generated KIM). Findings indicate that different critique activities can promote the use of different criteria for critique. Results suggest that the combination of generating and critiquing KIMs can support integrating evolution ideas but can be time-consuming. As time in biology classrooms is limited, study 3 distinguishes the learning effects from either generating or critiquing KIMs as more time efficient embedded learning tools. Findings suggest that critiquing KIMs can be more time efficient than generating KIMs. Using KIMs that include common alternative ideas for critique activities can create genuine opportunities for students to critically reflect on new and existing ideas. Critiquing KIMs can encourage knowledge integration by fostering self-monitoring of students’ learning progress, identifying knowledge gaps, and distinguishing alternative evolution ideas. This dissertation research demonstrates that science instruction of complex topics, such as human evolution, can succeed through a combination of scaffolded inquiry activities using dynamic visualizations, explanation activities, and collaborative KIM activities. This research contributes to educational research and practice by describing ways to make KIMs effective and time efficient learning tools for evolution education. Supporting students’ building of a more coherent understanding of core ideas of biology can foster their life-long interest and learning of science

Cryptography in Grade 10: Core Ideas with Snap! and Unplugged

International audienceWe report our experience of an extracurricular online intervention on cryptography in Grade 10. Our first goal is to describe how we taught some fundamental cryptography ideas by making students encounter a progression of representative cryptosystems, from classical to modern, and discover their characteristics and limitations. We used Snap! (a visual programming language) to realize hands-on activities: block-programming playgrounds (a form of task-specific programming languages) to experiment with cryptosystems, and an interactive app to support an unplugged (albeit remote) Diffie-Hellman key agreement. After experimenting with each system, the students were involved in a Socratic discussion on how to overcome the discovered limitations, motivating the introduction of the following system in our path. Our second goal is to evaluate the students' perceptions and learning of cryptography core ideas. They appreciated the course and felt that, despite being remote, it was fun and engaging. According to the students, the course helped them understand the role of cryptography, CS, and Math in society and sparked their interest in cryptography and CS. The final assessment showed that the students well understood the cryptography ideas addressed. Our third goal is to discuss what worked and areas of improvement. The "remote-unplugged" Diffie-Hellman, where the meeting chat was a metaphor for the public channel, engaged the students in understanding this groundbreaking protocol. Overall, they praised the activities as engaging, even when challenging. However, a strong "instructor blindness" induced by remote teaching often prevented us from giving the students the right amount of guidance during the exploration activities

A study of novice programmer performance and programming pedagogy.

Identifying and mitigating the difficulties experienced by novice programmers is an active area of research that has embraced a number of research areas. The aim of this research was to perform a holistic study into the causes of poor performance in novice programmers and to develop teaching approaches to mitigate them. A grounded action methodology was adopted to enable the primary concepts of programming cognitive psychology and their relationships to be established, in a systematic and formal manner. To further investigate novice programmer behaviour, two sub-studies were conducted into programming performance and ability. The first sub-study was a novel application of the FP-Tree algorithm to determine if novice programmers demonstrated predictable patterns of behaviour. This was the first study to data mine programming behavioural characteristics rather than the learner’s background information such as age and gender. Using the algorithm, patterns of behaviour were generated and associated with the students’ ability. No patterns of behaviour were identified and it was not possible to predict student results using this method. This suggests that novice programmers demonstrate no set patterns of programming behaviour that can be used determine their ability, although problem solving was found to be an important characteristic. Therefore, there was no evidence that performance could be improved by adopting pedagogies to promote simple changes in programming behaviour beyond the provision of specific problem solving instruction. A second sub-study was conducted using Raven’s Matrices which determined that cognitive psychology, specifically working memory, played an important role in novice programmer ability. The implication was that programming pedagogies must take into consideration the cognitive psychology of programming and the cognitive load imposed on learners. Abstracted Construct Instruction was developed based on these findings and forms a new pedagogy for teaching programming that promotes the recall of abstract patterns while reducing the cognitive demands associated with developing code. Cognitive load is determined by the student’s ability to ignore irrelevant surface features of the written problem and to cross-reference between the problem domain and their mental program model. The former is dealt with by producing tersely written exercises to eliminate distractors, while for the latter the teaching of problem solving should be delayed until the student’s program model is formed. While this does delay the development of problem solving skills, the problem solving abilities of students taught using this pedagogy were found to be comparable with students taught using a more traditional approach. Furthermore, monitoring students’ understanding of these patterns enabled micromanagement of the learning process, and hence explanations were provided for novice behaviour such as difficulties using arrays, inert knowledge and “code thrashing”. For teaching more complex problem solving, scaffolding of practice was investigated through a program framework that could be developed in stages by the students. However, personalising the level of scaffolding required was complicated and found to be difficult to achieve in practice. In both cases, these new teaching approaches evolved as part of a grounded theory study and a clear progression of teaching practice was demonstrated with appropriate evaluation at each stage in accordance with action researc

Learning to Teach from Anticipating Lessons through Comics-Based Approximations of Practice.

Teaching is complex and relational work that involves teacher’s interactions with individual or multiple students around the subject matter. It has been argued that observation experiences (e.g. field placement or watching video clips) are not sufficient to help prospective teachers to develop knowledge of teaching. This study aims to identify, examine, and illustrate the ways in which comics-based representations of teaching facilitate prospective teachers’ learning to teach. Specifically, the author explored how the use of a technology supported lesson-sketching tool, Depict, enabled prospective secondary mathematics teachers to attend to mathematical interactions between teacher and students in instruction when anticipating the development of a lesson. Drawing resources from Systemic Functional Linguistics, the author examined the ways in which anticipations of classroom interaction about a planned lesson differ when the anticipation was done using the Depict tool as compared with talking through the written lesson plan. Using case study methodology, the study investigated the aspects of the teaching work prospective teachers attended to when engaged in depicting a lesson, and observed the ways in which prospective teachers employed the graphic resources to support their lesson depiction. The results reveal that prospective teachers using Depict tool to create comics-based lesson slideshows immersed themselves in classroom settings and demonstrated their capacity to incorporate detailed teacher instructional actions, student reactions and mathematical tasks in their lessons. The prospective teachers unpacked their planned discrete class activities and attended to the relational nature among teacher, students and mathematics in instruction. The study indicates that the anticipation of a lesson, through creation of comics-based lesson depiction, could be a learning opportunity that approximates the interactive nature of teaching practice. The study suggests that comics-based representations of teaching can be seen as semiotic resources that mediate prospective teachers’ generation of teacher-student moment-to-moment class interactions, and facilitate their attention to instructional issues they have not previously been aware of. The study also implies that in order to engage prospective teachers in learning to do the work of teaching, teacher educators should consider directing prospective teachers’ attention to issues of temporality, multimodality and multivocality in instruction.Ph.D.Educational StudiesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/91421/1/chialc_1.pd