Techn. Hochsch., Diss., 2000--Aachen.

Universiẗat, Diss., 2002--Stuttgart. / Erscheinungsjahr an der Haupttitelstelle: 2002.

Techn. University, Diss., 2003--Darmstadt.

Techn. University, Diss., 2002--Darmstadt.

Universiẗat, Diss., 2003--Kassel.

University, Diss., 2004--Freiburg (Breisgau).

Software development teams are often geographically distributed from their customers and end users. This creates significant communication and coordination challenges that impact the effectiveness of requirements engineering. Travel costs, and the local availability of quality technical staff increase the demand for effective distributed software development teams. In this research an empirical study was conducted on the application of groupware to facilitate the requirements phase of the software engineering life cycle. The study considered the impact of the distributed work environment on requirements engineering process quality, as well as the effectiveness of requirements elicitation techniques when used in the distributed setting. Through the examination of the effectiveness of groupware tools, and requirements elicitation techniques, customer participation is found to be paramount for distributed requirements engineering. As requirements negotiation becomes more asynchronous in nature, it appears that customer participation in the elicitation process becomes very important for process effectiveness. Verbal communication barriers negatively effect customer participation. Such barriers cause customers to rely upon mediums such as email and text chat that are very good at reducing social distance, but are less rich in informational content. / Master of Science

This thesis reports a research effort that comprises six papers and a cover paper. In essence, the thesis contributes to the understanding of collaborative settings by introducing the perspective of 'places of collaboration‘. This perspective is particularly important when designing computer-based technologies that support collaborative settings. The starting point and overall research aim is to understand people‘s efforts to configure their current context for the purposes of collaboration. The cover paper of the thesis comprises a theoretical reflection and examination of four collaborative settings. The settings have been studied in situ through ethnographic inquiry and the results are reported in the six papers enclosed in the thesis. In my theoretical reflection, the concepts of 'place‘, 'space‘ and 'boundary objects‘ are central. The studies revealed that people‘s efforts to configure the current context create and reflect a 'place of collaboration‘. In other words, the effort to configure the context results in a practice characterized by an understanding of how to cooperate; a collaborative practice that constitutes a 'place of collaboration‘. During this configuration, the space and the use of materiality in this space are important parts in the creation of a place of collaboration. In addition, people configure collaborative contexts of intersecting practices by creating boundary objects. Boundary objects serve as mediators in a place-making process for the integration of places into a 'place of collaboration‘ for several practices. What is more, the dynamics of a place of collaboration may affect changes in existing modes of working and in computer-based tools that have been introduced into the workplace. The people and practices that constitute the place will in turn re-configure the place of collaboration, including the space and objects available due to the new circumstances. People‘s configuration of their current context reveals crucial aspects about the place of collaboration that must be considered also when designing to support this setting. However, this configuration may not necessarily equal efficiency and effectiveness, as evaluated by actors external to this context. The conclusion of this thesis is that future research and design should consider how to support people in their own effort to configure their collaborative context.

Webcasts are an emerging technology enabled by the expanding availability and capacity of the World Wide Web. This has led to an increase in the number of lectures and academic presentations being broadcast over the Internet. Ideally, repositories of such webcasts would be used in the same manner as libraries: users could search for, retrieve, or browse through textual information. However, one major obstacle prevents webcast archives from becoming the digital equivalent of traditional libraries: information is mainly transmitted and stored in spoken form. Despite voice being currently present in all webcasts, users do not benefit from it beyond simple playback. My goal has been to exploit this information-rich resource and improve webcast users' experience in browsing and searching for specific information. I achieve this by combining research in Human-Computer Interaction and Automatic Speech Recognition that would ultimately see text transcripts of lectures being integrated into webcast archives. In this dissertation, I show that the usefulness of automatically-generated transcripts of webcast lectures can be improved by speech recognition techniques specifically addressed at increasing the accuracy of webcast transcriptions, and the development of an interactive collaborative interface that facilitates users' contributions to machine-generated transcripts. I first investigate the user needs for transcription accuracy in webcast archives and show that users' performance and transcript quality perception is affected by the Word Error Rate (WER). A WER equal to or less than 25% is acceptable for use in webcast archives. As current Automatic Speech Recognition (ASR) systems can only deliver, in realistic lecture conditions, WERs of around 45-50%, I propose and evaluate a webcast system extension that engages users to collaborate in a wiki manner on editing imperfect ASR transcripts. My research on ASR focuses on reducing the WER for lectures by making use of available external knowledge sources, such as documents on the World Wide Web and lecture slides, to better model the conversational and the topic-specific styles of lectures. I show that this approach results in relative WER reductions of 11%. Further ASR improvements are proposed that combine the research on language modelling with aspects of collaborative transcript editing. Extracting information about the most frequent ASR errors from user-edited partial transcripts, and attempting to correct such errors when they occur in the remaining transcripts, can lead to an additional 10 to 18% relative reduction in lecture WER.

<p>Purpose: The objective of this study is to illustrate how participants in leaderless based projects communicate with each other. Several studies have focused on technology-supported projects, such as open source projects, with an established project manager and goal. There is a lack, to the best of our knowledge, in studies that deal with the communication pattern in a leaderless computer supported collaborative project.</p><p>Method: We have chosen to use a quantitative method where we systematically group several messages according to their content. This method was used in a similar study to illustrate the communication between participants involved in an open source project. We have taken the same Kripendorff based method and adapted it to our study by adding more descriptive variables.</p><p>Theoretical perspectives: Manuel Castell discusses the aspects of a new communication power that is rooted in the individual as part of a larger creative audience. The collaborative works we have studies are prime examples of how the creative audience works together and of mass self‐communication. In order to analyze the potential motivations behind the participant’s involvement in these collaborative works, we have adopted the ideas of Preece and Shneidermans frame theory. They have identified 4 major roles in most onlinebased co‐operations and refer to them as reader, contributor, collaborator and leader.</p><p>Result: Our results show that the communication in computer supported collaborative works is characterized by positive and energetic communication. The participants are all involved by their own will; they contribute because they want to. We believe this to be the major factor influencing the flow and form of communication between the participants. The majority of posts are comments to other participants or contributing posts that add to the progression of the discourse. We also have reason to believe that the use of smileys and embedded pictures is related to the tools available to the participants; the quicker and easier it is to add a picture the more likely the participants will use these tools.</p>