A full-day of presentations and collaborative sessions to study:


This workshop will focus on design evaluation for educators involved in introducing object-oriented *design* at an early point in computer science education. This will continue the work begun at OOPSLA 1998 with our first workshop on this topic, which resulted in a valuable conceptual model for understanding design evaluation. We now seek to further develop the work by using the model to structure advice for educators on how best to evaluate design for a variety of situations.

Design evaluation is an important subject both from the perspective of software engineering, and the perspective of pedagogy. Students must understand that any design has consequences, and they must themselves learn how to determine good and bad consequences that may flow from design decisions. Educators must lead students through this process, facilitate their learning, and also provide critical guidance.

Our work on design evaluation stems from our earlier work exploring and promoting the early emphasis on design as an important step forward in OO education. A 1996 workshop resulted in general agreement about the advantages of the approach, but also identified some key barriers to progress. In particular, we foresaw difficulties concerning *evaluating* design at an early stage. We began to tackle this in our 1998 workshop, and the main result was a conceptual model for design evaluation. The model clarifies the role of evaluation within the overall development process, with summative evaluation useful to implementors who need to assess designs, and formative evaluation useful to designers who wish to improve designs. Evaluation must be with respect to particular values, and we identified several alternatives, and enumerated various design representations, design evaluation mechanisms, and feedback methods.

We have made an excellent start, but there is much yet to be done. The alternatives for representation, evaluation and feedback all need to be better related to appropriate values, to help make appropriate choices to evaluate for particular design values. We also need to address the issue of summative evaluation in more detail. While the feedback loop makes formative evaluation attractive, summative evaluation is important beyond the design process itself. Understanding summative evaluation better would lead to better advice for people choosing between designs, and also help to assess the performance of designers. For educators, this would address this issue of student assessment. Finally, we need to determine how to test and verify these approaches.

Prospective 1999 workshop participants will be invited to submit a position paper with a contribution on this topic. The workshop will consist of presentations of these papers in the morning session, followed by an afternoon session of discussion and collaboration on the basis of the presentations from the morning. As before, we will prepare a report summarizing the workshop and results for the OOPSLA addendum, and make workshop papers and related resources available via our web repository. We also hope to be able again to present an immediate report to the OOPSLA Educators Symposium.

We will stay true to the key principles of our earlier workshops by continuing to stress design over implementation, explicitly avoiding language wars, and above all working to help educators perform their role more successfully. We again specifically invite people from industry to contribute their perspective.