Investigating the Quality Aspects of Crowd-Sourced Developer Forum: A Case Study of Stack Overflow

Technical question and answer (Q&A) websites have changed how developers seek information on the web and become more popular due to the shortcomings in official documentation and alternative knowledge sharing resources. Stack Overflow (SO) is one of the largest and most popular online Q&A websites for developers where they can share knowledge by answering questions and learn new skills by asking questions. Unfortunately, a large number of questions (up to 29%) are not answered at all, which might hurt the quality or purpose of this community-oriented knowledge base. In this thesis, we first attempt to detect the potentially unanswered questions during their submission using machine learning models. We compare unanswered and answered questions quantitatively and qualitatively. The quantitative analysis suggests that topics discussed in the question, the experience of the question submitter, and readability of question texts could often determine whether a question would be answered or not. Our qualitative study also reveals why the questions remain unanswered that could guide novice users to improve their questions. During analyzing the questions of SO, we see that many of them remain unanswered and unresolved because they contain such code segments that could potentially have programming issues (e.g., error, unexpected behavior); unfortunately, the issues could always not be reproduced by other users. This irreproducibility of issues might prevent questions of SO from getting answers or appropriate answers. In our second study, we thus conduct an exploratory study on the reproducibility of the issues discussed in questions and the correlation between issue reproducibility status (of questions) and corresponding answer meta-data such as the presence of an accepted answer. According to our analysis, a question with reproducible issues has at least three times higher chance of receiving an accepted answer than the question with irreproducible issues. However, users can improve the quality of questions and answers by editing. Unfortunately, such edits may be rejected (i.e., rollback) due to undesired modifications and ambiguities. We thus offer a comprehensive overview of reasons and ambiguities in the SO rollback edits. We identify 14 reasons for rollback edits and eight ambiguities that are often present in those edits. We also develop algorithms to detect ambiguities automatically. During the above studies, we find that about half of the questions that received working solutions have negative scores. About 18\% of the accepted answers also do not score the maximum votes. Furthermore, many users are complaining against the downvotes that are cast to their questions and answers. All these findings cast serious doubts on the reliability of the evaluation mechanism employed at SO. We thus concentrate on the assessment mechanism of SO to ensure a non-biased, reliable quality assessment mechanism of SO. This study compares the subjective assessment of questions with their objective assessment using 2.5 million questions and ten text analysis metrics. We also develop machine learning models to classify the promoted and discouraged questions and predict them during their submission time. We believe that the findings from our studies and proposed techniques have the potential to (1) help the users to ask better questions with appropriate code examples, and (2) improve the editing and assessment mechanism of SO to promote better content quality

Online customer experience in an emerging e-retail market

Although customer experience has attracted significant attention in marketing theorizing for over three decades, research has barely progressed beyond the traditional conceptualizations of the concept. Specifically, research on multichannel retailing experience is scarce and fragmented despite previous calls to investigate how customer experience can be optimized at different channels. Additionally, although eWOM is fast supplanting traditional WOM as a determinant of consumer behavior whilst Internet platforms have been declared the future fronts for successful customer relationship management, previous studies rarely examined how consumers process and integrate multiple online reviews especially dissatisfied eWOM. Extrapolating from the foregoing, the following research question is posed: “How can online retailers exploit the link between previous shopping experiences and perceived credibility of negative experience reviews (PCoNERs) to enhance consumer-firm relationship quality?”To answer the above research question, an experience-perception-attitude model was built on the foundations of two social cognitive psychology theories (i.e. the schema theory and the elaboration likelihood model (ELM)) and consequently tested through four scenario-based experiments mapped out into one pilot study and two main studies. The pilot study and study 1 utilized a 2 × 2 between-subject factorial design while study 2 employed 2 × 2 × 2 between-subject factorial design. Data was generated from undergraduate and postgraduate students recruited from two universities located in southern Nigeria. Exploratory factor analysis, partial least squares structural equation modelling procedure, independent sample t-test, Chi-square, one-way analysis of variance, and multivariate analysis of variance were the analytical techniques utilized.Five major contributions are made. First, the thesis developed and tested a unique experience-perception-attitude model from the perspective of two social cognitive psychology theories. The experience-perception-attitude model not only portrayed the multi-channel character of online customer experience but also advanced Verhoef et al.’s (2009) holistic and dynamic model of customer experience by demonstrating how consumer-firm relationship quality can be enhanced through a simultaneous consideration of shopping experiences emanating from both company website and social media site. Second, the thesis extends the context-specific nature of customer experience by demonstrating that emotional experience is the most important driver of PCoNERs in a recession-ridden emerging e-retailing market. Third, the study advances the eWOM literature and ELM by drawing on the ELM to demonstrate that PCoNERs have negative effect on consumer-firm relationship quality; while also demonstrating that the effects of the two thresholds of elaboration (i.e. review source credibility and review frequency) become infinitesimal if consumers are exposed to reviews with consistent valence. Fourth, the thesis adds to the experimental design technique utilized by channel integration researchers and previous panel data-based studies by drawing on the netnographic research approach to utilize naturalistic narratives as experimental scenarios. Finally, the findings offer an evidence-based guide on how e-retailers can practically engage in the systematic management of customer clues. The findings will also assist all categories of e-retailers determine the strategic position to pursue based on their resources and capabilities

Facilitating Efficient Information Seeking in Social Media

abstract: Online social media is popular due to its real-time nature, extensive connectivity and a large user base. This motivates users to employ social media for seeking information by reaching out to their large number of social connections. Information seeking can manifest in the form of requests for personal and time-critical information or gathering perspectives on important issues. Social media platforms are not designed for resource seeking and experience large volumes of messages, leading to requests not being fulfilled satisfactorily. Designing frameworks to facilitate efficient information seeking in social media will help users to obtain appropriate assistance for their needs and help platforms to increase user satisfaction. Several challenges exist in the way of facilitating information seeking in social media. First, the characteristics affecting the user’s response time for a question are not known, making it hard to identify prompt responders. Second, the social context in which the user has asked the question has to be determined to find personalized responders. Third, users employ rhetorical requests, which are statements having the syntax of questions, and systems assisting information seeking might be hindered from focusing on genuine questions. Fouth, social media advocates of political campaigns employ nuanced strategies to prevent users from obtaining balanced perspectives on issues of public importance. Sociological and linguistic studies on user behavior while making or responding to information seeking requests provides concepts drawing from which we can address these challenges. We propose methods to estimate the response time of the user for a given question to identify prompt responders. We compute the question specific social context an asker shares with his social connections to identify personalized responders. We draw from theories of political mobilization to model the behaviors arising from the strategies of people trying to skew perspectives. We identify rhetorical questions by modeling user motivations to post them.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

The design, implementation and evaluation of a web-based learning environment for distance education

In this study, the need was emphasised to investigate the effects of using the Web in teaching students at a distance using a multi-level evaluation framework. A Web-based learning environment was designed, developed, implemented and evaluated for this purpose. Constructivist epistemology provided the basis for developing various components and developing problem-centred and interactive activities. Management, tutorial, interaction and support components were designed to work with each other to construct the learning environment, deliver course content, facilitate interaction and monitor student progress.A methodology was designed to describe and assess the learning environment in terms of access (standardisation, speed, resources, the tutor and peers), costs (types, structure, factors influencing, etc.), teaching and learning functions (quality of course objectives, materials and resources, learning approach and student achievement), interactivity (quantity and quality of student-tutor and student-peer interaction), user-friendliness (user-interface design, ease of use and navigation design) and organisational issues. The learners were Egyptian first-grade secondary school students (32), assigned randomly, and the topic selected for the course being developed was mathematics. Feedback was obtained from both learners and experts in distance education and on-line learning during the developmental and field-testing of the learning environment. Quantitative and qualitative methods (on-line student and expert questionnaires, students' logs, performance in formative evaluation, content analysis of peer discussions, achievement test and cost-analysis) were combined to gain insights into students' satisfaction with the different instructional and technical features and capabilities of the learning environment, achievement of course objectives in comparison with conventional classroom students, factors influencing their learning and perceptions and the unit cost per student study hour.The results indicated that although the learning environment and course materials were accessible, interactive, well-structured, user-friendly and achievement was successful for the on-line group, no significant differences were identified between the on-line students and traditional classroom students in overall achievement or achievement of low-order and high-order learning objectives. In addition, it is unlikely any cost saving would be made from shifting to the Internet to deliver instruction and many major factors were found to influence the development and support costs of on-line learning

National evaluation of Partnerships for Older People Projects

Executive Summary The Partnership for Older People Projects (POPP) were funded by the Department of Health to develop services for older people, aimed at promoting their health, well-being and independence and preventing or delaying their need for higher intensity or institutional care. The evaluation found that a wide range of projects resulted in improved quality of life for participants and considerable savings, as well as better local working relationships. • Twenty-nine local authorities were involved as pilot sites, working with health and voluntary sector partners to develop services, with funding of £60m • Those projects developed ranged from low level services, such as lunch-clubs, to more formal preventive initiatives, such as hospital discharge and rapid response services • Over a quarter of a million people (264,637) used one or more of these services • The reduction in hospital emergency bed days resulted in considerable savings, to the extent that for every extra £1 spent on the POPP services, there has been approximately a £1.20 additional benefit in savings on emergency bed days. This is the headline estimate drawn from a statistically valid range of £0.80 to £1.60 saving on emergency bed days for every extra £1 spent on the projects. • Overnight hospital stays were seemingly reduced by 47% and use of Accident & Emergency departments by 29%. Reductions were also seen in physiotherapy/occupational therapy and clinic or outpatient appointments with a total cost reduction of £2,166 per person • A practical example of what works is pro-active case coordination services, where visits to A&E departments fell by 60%, hospital overnight stays were reduced by 48%, phone calls to GPs fell by 28%, visits to practice nurses reduced by 25% and GP appointments reduced by 10% • Efficiency gains in health service use appear to have been achieved without any adverse impact on the use of social care resources • The overwhelming majority of the POPP projects have been sustained, with only 3% being closed – either because they did not deliver the intended outcomes or because local strategic priorities had changed • PCTs have contributed to the sustainability of the POPP projects within all 29 pilot sites. Moreover, within almost half of the sites, one or more of the projects are being entirely sustained through PCT funding – a total of 20% of POPP projects. There are a further 14% of projects for which PCTs are providing at least half of the necessary ongoing funding • POPP services appear to have improved users’ quality of life, varying with the nature of individual projects; those providing services to individuals with complex needs were particularly successful, but low-level preventive projects also had an impact • All local projects involved older people in their design and management, although to varying degrees, including as members of steering or programme boards, in staff recruitment panels, as volunteers or in the evaluation • Improved relationships with health agencies and the voluntary sector in the locality were generally reported as a result of partnership working, although there were some difficulties securing the involvement of GP

Probabilistic Graphical Models for Credibility Analysis in Evolving Online Communities

One of the major hurdles preventing the full exploitation of information from online communities is the widespread concern regarding the quality and credibility of user-contributed content. Prior works in this domain operate on a static snapshot of the community, making strong assumptions about the structure of the data (e.g., relational tables), or consider only shallow features for text classification. To address the above limitations, we propose probabilistic graphical models that can leverage the joint interplay between multiple factors in online communities --- like user interactions, community dynamics, and textual content --- to automatically assess the credibility of user-contributed online content, and the expertise of users and their evolution with user-interpretable explanation. To this end, we devise new models based on Conditional Random Fields for different settings like incorporating partial expert knowledge for semi-supervised learning, and handling discrete labels as well as numeric ratings for fine-grained analysis. This enables applications such as extracting reliable side-effects of drugs from user-contributed posts in healthforums, and identifying credible content in news communities. Online communities are dynamic, as users join and leave, adapt to evolving trends, and mature over time. To capture this dynamics, we propose generative models based on Hidden Markov Model, Latent Dirichlet Allocation, and Brownian Motion to trace the continuous evolution of user expertise and their language model over time. This allows us to identify expert users and credible content jointly over time, improving state-of-the-art recommender systems by explicitly considering the maturity of users. This also enables applications such as identifying helpful product reviews, and detecting fake and anomalous reviews with limited information.Comment: PhD thesis, Mar 201

Building Relationships between Fans and Teams in the National Basketball Association through Facebook: The Influence of Engagement on Relationship Quality and Consumer Behavior

The purpose of this study was to investigate the relationships between National Basketball Association fans' engagement with their favorite teams' Facebook pages, fans' relationship quality with their favorite team, and their purchase and referral intentions using relationship marketing as a framework. Additionally, the types of content fans preferred teams post on Facebook were examined. Two convenience samples, one collected by posting a link to Facebook and the other by purchasing a Qualtrics panel, were collected. Data were analyzed using confirmatory factor analysis, structural equation modeling, and frequency tables. Results indicated in both samples that individuals who engaged more on Facebook also had greater relationship quality. Additionally, in the Qualtrics panel, a higher level of engagement with teams' Facebook page had a statistically significant, positive impact on purchase intentions. In both samples, the indirect effects of Facebook engagement on purchase and referral intentions as mediated by relationship quality were statistically significant and positive, suggesting more engaged individuals on Facebook had higher relationship quality and were more likely to intend to purchase tickets and merchandise in the future and refer others to do the same. Overall, respondents indicated they preferred content related to players, including injury and movement, as well as score-related posts, suggesting they might prefer using Facebook as another way to receive information instead of choosing to actively engage with their favorite team. However, because results from modeling suggest engaging individuals on Facebook has positive impacts on future behavioral intentions, sport marketers should consider engaging individuals on Facebook while still fulfilling their need for information about players and game results

EFFECTS OF ONLINE REPUTATION MECHANISMS ON PERCEIVED CREDIBILITY AND HEALTH DECISION MAKING

Reputation mechanisms and credibility are methods of adding additional information to forum posts, and are becoming more commonplace in online health forums. These systems provide users of forums additional information which can be used to evaluate the trustworthiness of the information being disseminated in community-run websites. The goal of the following studies is twofold. First, it is necessary to identify which elements of reputation systems and credibility participants use to make assessments of the trustworthiness, perceived credibility, and perceived accuracy of answers to health-related questions on a simulated web forum. Once the reputation mechanisms and credibility systems have been identified, the second study explored how high and low overall reputation affects decisions in a non-compensatory decision-making task. This study demonstrated a preference for a non-dominating alternative when it is associated with high reputation, and an overwhelming preference for a dominating alternative when associated with a high reputation. This study also showed that participants expressed higher levels of perceived credibility, trust, confidence, and accuracy of answers when making a decision based on reputation rather than utility

Antecedents of travellers' eWOM communication

Development of the internet and electronic media provide a convenient platform for travellers to instantly share their experiences. Known as electronic word-of-mouth (eWOM), it offers a powerful source of information and can also act as an effective marketing tool. Existing studies have focused on the conceptualisation and influences of eWOM communication, but limited attention has been given to the antecedents of it from the attitUdinal perspective within the tourism industry. This study aims to fulfil that gap. Data from international travellers having experience of eWOM communication was collected through online focus groups and survey questionnaire. Content analysis and structural equation modelling were employed for data analysis respectively. Based on the literature review and online focus group findings three key antecedents were identified, being: Adoption of Electronic Communication Technology, Motivation for eWOM Communication and Subjective Norm. Thereafter, a conceptual framework was proposed to bring these three antecedents together for the first time. This was empirically tested, particularly examining the influences of the overall attitude and behavioural intention of eWOM communication. Survey results showed that the overall attitude towards eWOM communication plays an important role in the understanding of the eWOM communication behaviour of travellers, serving as a mediator between antecedents and behavioural intention. From the theoretical perspective, this study fulfils the research gap through exploring the antecedents of eWOM communication from the attitudinal perspective. A new conceptual framework is therefore empirically validated providing the basis for replication within future studies. Through employing the Technology Acceptance Model, Functional Theory of Attitude, Subjective Norm and Consumer Attitude, this study contributes to extending those theories in the context of eWOM communication within the tourism industry. Regarding managerial implications, this research identifies the antecedents of eWOM communication behaviour of travellers, which could help practitioners stimu