An Empirical Study of Fault Localization for End-User Programmers

End users develop more software than any other group of programmers, using software authoring devices such as e-mail filtering editors, by-demonstration macro builders, and spreadsheet environments. Despite this, there has been little research on finding ways to help these programmers with the dependability of their software. We have been addressing this problem in several ways, one of which includes supporting end-user debugging activities through fault localization techniques. This paper presents the results of an empirical study conducted in an end-user programming environment to examine the impact of two separate factors in fault localization techniques that affect technique effectiveness. Our results shed new insights into fault localization techniques for end-user programmers and the factors that affect them, with significant implications for the evaluation of those techniques.

Perceptions of Procedural and Distributive Justice in the September 11th Victim Compensation Fund

The September l1th Victim Compensation Fund (the Fund) was created in response to the terrorist attacks of September 11, 2001. Much has been written about the Fund, both pro and con, in both popular media and scholarly literature. Perhaps the most widely used term in referring to the Fund is "unprecedented." The Fund is intriguing for many reasons, particularly for its public policy implications and its impact on the claimants themselves. The federal government has never before provided compensation to victims of terrorism through a special master who had virtually unlimited discretion in determining awards. Consequently, this formal allocation of money by a representative of the federal government to its citizens has provided an opportunity to test theories of procedural and distributive justice in a novel context. This article tests these theories by analyzing the results of a study of the Fund's claimants. Part I provides general background, summarizes existing commentary on the Fund, and discusses prior research on social justice that is relevant to the 9/11 claimants' experiences with the Fund. Part II of this article describes the methodology behind the study, in which seventy-one individuals who filed claims with the Fund completed surveys about their experiences with and perceptions of the Fund. Part III discusses the survey results. We found that participants were reasonably satisfied with the procedural aspects of the Fund, such as representatives' impartiality and respectful treatment. Participants were less satisfied, however, with the distributive aspects of the Fund, such as the unequal distribution of compensation and the reduction in compensation if claimants received compensation from other sources (e.g., life insurance). Part IV of this article addresses the implications of the study results for public policy and for theories of social justice.

Incorporating Varying Test Costs and Fault Severities into Test Case Prioritization

Test case prioritization techniques schedule test cases for regression testing in an order that increases their ability to meet some performance goal. One performance goal, rate offault detection, measures how quickly faults are detected within the testing process. In previous work we provided a metric, APFD, for measuring rate of fault detection, and techniques for prioritizing test cases to improve APFD, and reported the results of experiments using those techniques. This metric and these techniques, however, applied only in cases in which test costs and fault severity are uniform. In this paper, we present a new metric for assessing the rate of fault detection of prioritized test cases, that incorporates varying test case and fault costs. We present the results of a case study illustrating the application of the metric. This study raises several practical questions that might arise in applying test case prioritization; we discuss how practitioners could go about answering these questions.