Comparing API Design Choices with Usability Studies: A Case Study and Future Directions

There are more APIs than ever, and designing APIs that are usable by their target audience is difficult. Work at Microso ft has demonstrated that run- ning controlled usability studies with participants from different personas and analyzing the results of these studies using the co gnitive dimensions framework is effective at identifying and preventing usabilit y problems in APIs. This paper presents a generalization of that technique in the form of usability studies of common API design choices. By studying a single design choice from multiple perspectives, we can generalize our results to any API that might be affected by the design choice. We show the feasibility of our approach with an initial study on whether or not to require constructor parameters , and present our current and planned work to study more API design choices.