Elizabeth Patitsas

The Canterbury QuestionBank: building a repository of multiple-choice CS1 and CS2 questions

In this paper, we report on an ITiCSE-13 Working Group that developed a set of 654 multiple-choice questions on CS1 and CS2 topics, the Canterbury QuestionBank. We describe the questions, the metadata we investigated, and some preliminary investigations of possible research uses of the QuestionBank. The QuestionBank is publicly available as a repository for computing education instructors and researchers.

Comparing and contrasting different algorithms leads to increased student learning

Comparing and contrasting different solution approaches is known in math education and cognitive science to increase student learning -- what about CS? In this experiment, we replicated work from Rittle-Johnson and Star, using a pretest--intervention--posttest--follow-up design (n=241). Our intervention was an in-class workbook in CS2. A randomized half of students received questions in a compare-and-contrast style, seeing different code for different algorithms in parallel. The other half saw the same code questions sequentially, and evaluated them one at a time. Students in the former group performed better with regard to procedural knowledge (code reading & writing), and flexibility (generating, recognizing & evaluating multiple ways to solve a problem). The two groups performed equally on conceptual knowledge. Our results agree with those of Rittle-Johnson and Star, indicating that the existing work in this area generalizes to CS education.

Effective closed labs in early CS courses: lessons from eight terms of action research

We report on best practices we have established to teach first-year computer science students in closed laboratories, founded on over three years of action research in a large introductory discrete mathematics and digital logic course. Our practices have resulted in statistically significant improvements in student and teaching assistant perception of the labs. Specifically, we discuss our practices of streamlining labs to reduce load on students that is extraneous to the labs learning goals; establishing a positive first impression for students and TAs in the early weeks of the term; and effectively managing the teaching staff, including weekly preparation meetings for TAs using and a gradual, iterative curriculum development cycle that engages all stakeholders in the course.

Early Developmental Activities and Computing Proficiency

As countries adopt computing education for all pupils from primary school upwards, there are challenging indicators: significant proportions of students who choose to study computing at universities fail the introductory courses, and the evidence for links between formal education outcomes and success in CS is limited. Yet, as we know, some students succeed without prior computing experience. Why is this? Some argue for an innate ability, some for motivation, some for the discrepancies between the expectations of instructors and students, and some -- simply -- for how programming is being taught. All agree that becoming proficient in computing is not easy. Our research takes a novel view on the problem and argues that some of that success is influenced by early childhood experiences outside formal education. In this study, we analyzed over 1300 responses to a multi-institutional and multi-national survey that we developed. The survey captures enjoyment of early developmental activities such as childhood toys, games and pastimes between the ages 0 --- 8 as well as later life experiences with computing. We identify unifying features of the computing experiences in later life, and attempt to link these computing experiences to the childhood activities. The analysis indicates that computing proficiency should be seen from multiple viewpoints, including both skill-level and confidence. Our analysis is the first to show, we believe, that particular early childhood experiences are linked to parts of computing proficiency, namely those related to confidence with problem solving using computing technology. These are essential building blocks for more complex use. We recognize issues in the experimental design that may prevent our data showing a link between early activities and more complex computing skills, and suggest adjustments for future studies. Ultimately, we expect that this line of research will feed in to early years and primary education, and thereby improve computing education for all.

Alternative Publishing and Dissemination of CS Education Research (Abstract Only)

Large volumes of Computer Science Educational (CS Ed) material are published every year but it is apparent that equally large volumes of this are not being read or having much impact on practice, or even available to the practitioners who could use it. How can we distribute CS Ed materials and information more effectively and in potentially innovative ways? This BOF will provide a platform for discussion on a selection of techniques that encourage discussion and dissemination of CS Ed techniques in the community. Is traditional publishing still a good approach or is it just part of a wider group of techniques?

Searching for Early Developmental Activities Leading to Computational Thinking Skills

Drawing on the long debate about whether computer science (CS) and computational thinking skills are innate or learnable, this working group is based on the following hypothesis: The apparent innate ability of some CS learners who succeed in CS courses despite no prior exposure to computing is a manifestation of early childhood experiences and learning outside formal education.

How CS departments are managing the enrolment boom: Troubling implications for diversity

Enrolments in North American undergraduate computer science have been booming in recent years, and many CS departments have been struggling to meet student demand. We surveyed 78 CS professors, instructors, staff, and administrators to see how the enrolment boom has been affecting their practice; and to see how departments are responding in terms of policy. We asked participants to tell us what factors were being considered in their departments policymaking using a page of open-ended questions. Only one participant of 78 noted diversity as a concern. We then gave them a list of factors we thought could affect their departments policymaking, including diversity. After this prompt, more participants reported diversity was important (n=5). We found that policymakers are favouring solutions which are intuitive to them, rather than looking for examples from the literature, similar institutions, or the history of their own institution. Problematically, many of these favoured approaches have historically been linked to having a negative impact on demographic diversity in CS programmes. This could exacerbate the low participation of underrepresented groups in computer science, and undermine efforts to improve diversity.

Investigating the effects of women-in-CS initiatives

There is a widespread desire to improve the numbers of women in CS, and as a result, a large number of well-intentioned initiatives targeting the issue. However, explicit interventions -- interventions which call attention to a minority being a minority -- can backfire, and actually harm attempts to improve diversity. In my work; I plan to study what unintentional, negative effects women-in-CS initiatives can have; and to give suggestions for mitigating them. I am in an early stage of my PhD, having had my topic approved by my committee and working toward implementing empirical studies.