Laura Marie Leventhal

Sleuthing in HyperHolmes : a TM an evaluation of using hypertext vs. a book to answer questions.

Abstract Although hypertext offers exciting new ways of presenting and accessing information, there is little research which systematically compares the usability of hypertext against traditional media with an eye to improving the design of the hypertext. This paper presents the results of an experiment which examined the performance and navigation strategies of users engaged in a question-answering task using either a hypertext encyclopedia of Sherlock Holmes facts (the HyperHolmessyTMstem) or the traditional paper form. The results showed that, overall, the hypertext users were marginally more accurate in answering questions, and excelled at questions where the key information was embedded in a text entry. The book users were marginally faster overall, but excelled only in answering questions based on graphics. Hypertext users showed a preference for those tools which most closely mimicked use of a conventional book. They used a hierarchical structure to guide their navigation strategy in early trials, ...

Hypertext or book: Which is better for answering questions?

An important issue in the evolution of hypertext is the design of such systems to optimally support user tasks such as asking questions. Few studies have systematically compared the use of hypertext to books in seeking information, and those that have been done have not found a consistent superiority for hypertext. In addition, designers developing hypertext books have few guidelines. In the present study, users performed information-seeking tasks and answered a variety of types of questions about Sherlock Holmes stories using either a conventional paper encyclopedia or a hypertext encyclopedia. The questions varied on the amount of information needed to derive an answer (fact or inference), the location of the question’s key phrase in the hypertext (enrry title or entry content), and the format of the information (text or map). Accuracy and time were recorded. The hypertext group excelled in answering fact questions where the information was embedded in a text entry. The book group excelled only in answering fact questions based on maps. In spite of having far more experience using books, the book group was not significantly faster overall and did not perform as well on an incidental learning task. Our results suggest that a hypertext book with a nonlinear structure and including a variety of navigational tools can equal or surpass conventional books as an information-seeking medium, even with minimal training.

Why software testing is sometimes ineffective: two applied studies of positive test strategy

The term positive test strategy describes the tendency to test a hypothesis with test cases that confirm (i.e., aim to support) rather than disconfirm the hypothesis. Most demonstrations of this phenomenon have involved relatively abstract problems. The authors suggest that people use a positive test strategy in a more applied setting as well, that is, in computer software testing. In 2 experiments, they examined how Ss with varying expertise performed functional testing of software. There was substantial evidence of the use of a positive test strategy: Ss tended to test only those functions and aspects of the software that were specifically described in the specifications as what the software was supposed to do. This effect was only partially mitigated by increasing expertise among testers and by more complete program specifications

Empirically-based re-design of a hypertext encyclopedia

This paper reports on the processes used and guidelines discovered in re-designing the user interface of the hypertext encyclopedia, HyperHolmes. The re-design was based on the outcomes of a previous experiment and was evaluated experimentally. Results showed that the new system resulted in superior performance and somewhat different styles of navigation compared to the old system and to paper. The study provides empirical support for design guidelines relating to tiled windows, navigation tools, graphics and hierarchical navigation.

Another view of computer science ethics: patterns of responses among computer scientists

Abstract Within the computer science community, issues of ethics have emerged as significant and critical concerns. However, as computer scientists, we have little empirical information about how we feel about computer science ethics. We review the literature related to our work: studies of the attitudes of computer scientists towards issues of ethics, studies of the effects of technical expertise on attitudes toward ethical issues, and studies of the effects of gender on attitudes toward ethical issues. We describe two studies of attitudes toward issues of ethics in computing. In Study I, we attempted to identify patterns of responses toward ethical issues in computer science, as well as the relationships between different levels of technical expertise and gender to patterns of responses. In Study II, we focused on changes in responses to ethical issues as computer science students gain technical expertise. We also investigated effects of gender on responses in Study II. We found that four patterns of responses occurred. We also demonstrated some differences in responses among subjects of different genders and levels of technical expertise.

A comparison of the usability and effectiveness of web-based delivery of instructions for inherently-3D construction tasks on handheld and desktop computers

Since its inception, VRML has held out the promise of initiating a quantum leap in web deliverable content and applications. However, the promise has yet to be realized. In this paper, we consider the problem of the web-based delivery of instructions for inherently-3D construction tasks. We describe a presentation that we built using VRML and discuss a comparative study of the effectiveness of the presentation when viewed using both a traditional desktop environment and also a handheld PDA. The study was both quantitative and qualitative and examined the effect of the user interface and delivery technology on overall task success, user interaction level, and task success for inherently 3D steps.

A CASE primer for computer science educators

The continuing demand for the development of new software and maintenance of existing software has made productivity an important issue in the software industry. In the past, increases in productivity have come from the introduction of software engineering techniques. Today, software engineers are looking to CASE (computer-aided software engineering) tools as a possible source of further improvements in productivity. This paper provides an overview of current CASE tools, with a focus on three types of tools: framing environments, programming environments and general environments. Two specific CASE systems are discussed in some detail. CASE systems in the context of software engineering education are also discussed.

Two for One: Squeezing Human-Computer Interaction and Software Engineering into a Core Computer Science Course

The final report of the Joint Task Force on Computing Curricula (CC2001) suggests that an updated computer science curricula must reflect the broadening nature of our discipline. Two areas that are included in the CC2001 are software engineering (SE) and human-computer interaction (HCI). While the first inclination might be to incorporate HCI concepts into a traditional SE course, we propose a different approach. This paper outlines a project-oriented HCI course in which we are able to emphasize some SE notions in the context of HCI concepts. Our course is also a maturation class for our students because they are exposed to a number of non-programming computer science activities, including project specification, software and interface design, user testing, prototyping and use of guidelines. We include an overview of course content that illustrates our approach. We also describe our coverage of specific CC2001 knowledge units and provide some feedback data for our course.

Positive Test Bias in Software Testing Among Professionals: A Review

Fundamental but virtually unexplored issues in human-computer interaction involve the roles of biases in software engineering tasks. In studies of naturalistic testing tasks, as well as ones which follow common laboratory models in this area, we have found ample evidence that testers have positive test bias. This bias is manifest as a tendency to execute about four times as many positive tests, designed to show that “the program works,” as tests which challenge the program. In our prior work, we have found that the expertise of the subjects, the completeness of the software specifications, and the presence/absence of program errors may reduce positive test bias. Skilled computer scientists invent specifications to test in the absence of actual specifications, but still exhibit positive test bias.

Implementations of the CC′01 human – computer interaction guidelines using Bloom's taxonomy

In todays technology-laden society human – computer interaction (HCI) is an important knowledge area for computer scientists and software engineers. This paper surveys existing approaches to incorporate HCI into computer science (CS) and such related issues as the perceived gap between the interests of the HCI community and the needs of CS educators. It presents several implementations of the HCI subset of the CC′01 curricular guidelines, targeting CS educators with varying degrees of HCI expertise. These implementations include course/module outlines from freshman to graduate levels, suggested texts, and project ideas and issues, such as programming languages and environments. Most importantly, each outline incorporates Blooms taxonomy to identify the depth of knowledge to be mastered by students. This paper condenses collaborative contributions of 26 HCI/CS educators aiming to improve HCI coverage in mainstream CS curricula.