The nature of volunterreed geographic information

This contribution starts from the assumption that volunteered geographic information is a technological, cultural and scientific innovation. It therefore offers first some general background on the context that has fuelled the development of VGI and the lively scientific debates that have accompanied its success. The paper then focuses on the nature of this data by describing the main elements of VGI: the geographical reference (coordinates, geotag, etc.), the contents (texts, images, etc.) and the producers’ profiles. The opportunities and the criticalities offered by this data are described with examples drawn from recent literature and applications to highlight both the research challenges and the current state of the subject. The chapter aims to provide a guide to and a reference picture of this rapidly evolving subject

Community Acknowledgment: Engaging Community Members in Volunteer Acknowledgment

Volunteers in non-profit groups are a valuable workforce that contributes to economic development and supports people in need in the U.S. However, many non-profit groups face challenges including engaging and sustaining volunteer participation, as well as increasing visibility of their work in the community. To support non-profit groups\u27 service, we explored how engaging community members in the volunteer-acknowledgment process may have an impact. We set up workstations and invited community members to write thank-you cards to volunteers in non-profit groups. We conducted 14 interviews with volunteers and community members, collected and analyzed 25 thank-you cards. We found that the acknowledgment activity can help circulate social goods through multiple stakeholders, that authenticity was valued in the acknowledgment process, and that non-profit groups intended to distribute, reuse, and publicize the acknowledgments to utilize them to a fuller extent. Our contributions include expanding knowledge on experiences, needs, and impact of community acknowledgment from different stakeholders, as well as presenting design opportunities

"I know where that is": Cultural Differences in Perception of Places

This study focuses on modeling people's perceptions of places and how those perceptions are affected by cultural differences. Cultural background affects the way people feel and recall information. However, it is unclear how cultural background influences individual's perception of geospatial areas such as a town or a city. One way an individual's cultural background varies is with regard to the patterns of one's routine communication. This concept is described by Hall's high- and low-context cultural model (1976). The ways people perceive geospatial places can be characterized in terms of their tendency to rely on specific landmarks or symbolic addresses. In this study, we use an online survey and an online place recognition game to test the hypothesis that high-context individuals will perceive urban places in terms of landmarks rather than symbolic addresses. The results suggest that high- and low-context is not a unified construct. Instead it is a multi-dimensional construct with sub-dimensions where one of those, i.e. one's attitude towards other's communication style, may affect an individual's perception of places

Spatial and Temporal Sentiment Analysis of Twitter data

The public have used Twitter world wide for expressing opinions. This study focuses on spatio-temporal variation of georeferenced Tweets’ sentiment polarity, with a view to understanding how opinions evolve on Twitter over space and time and across communities of users. More specifically, the question this study tested is whether sentiment polarity on Twitter exhibits specific time-location patterns. The aim of the study is to investigate the spatial and temporal distribution of georeferenced Twitter sentiment polarity within the area of 1 km buffer around the Curtin Bentley campus boundary in Perth, Western Australia. Tweets posted in campus were assigned into six spatial zones and four time zones. A sentiment analysis was then conducted for each zone using the sentiment analyser tool in the Starlight Visual Information System software. The Feature Manipulation Engine was employed to convert non-spatial files into spatial and temporal feature class. The spatial and temporal distribution of Twitter sentiment polarity patterns over space and time was mapped using Geographic Information Systems (GIS). Some interesting results were identified. For example, the highest percentage of positive Tweets occurred in the social science area, while science and engineering and dormitory areas had the highest percentage of negative postings. The number of negative Tweets increases in the library and science and engineering areas as the end of the semester approaches, reaching a peak around an exam period, while the percentage of negative Tweets drops at the end of the semester in the entertainment and sport and dormitory area. This study will provide some insights into understanding students and staff ’s sentiment variation on Twitter, which could be useful for university teaching and learning management

European Handbook of Crowdsourced Geographic Information

This book focuses on the study of the remarkable new source of geographic information that has become available in the form of user-generated content accessible over the Internet through mobile and Web applications. The exploitation, integration and application of these sources, termed volunteered geographic information (VGI) or crowdsourced geographic information (CGI), offer scientists an unprecedented opportunity to conduct research on a variety of topics at multiple scales and for diversified objectives. The Handbook is organized in five parts, addressing the fundamental questions: What motivates citizens to provide such information in the public domain, and what factors govern/predict its validity?What methods might be used to validate such information? Can VGI be framed within the larger domain of sensor networks, in which inert and static sensors are replaced or combined by intelligent and mobile humans equipped with sensing devices? What limitations are imposed on VGI by differential access to broadband Internet, mobile phones, and other communication technologies, and by concerns over privacy? How do VGI and crowdsourcing enable innovation applications to benefit human society? Chapters examine how crowdsourcing techniques and methods, and the VGI phenomenon, have motivated a multidisciplinary research community to identify both fields of applications and quality criteria depending on the use of VGI. Besides harvesting tools and storage of these data, research has paid remarkable attention to these information resources, in an age when information and participation is one of the most important drivers of development. The collection opens questions and points to new research directions in addition to the findings that each of the authors demonstrates. Despite rapid progress in VGI research, this Handbook also shows that there are technical, social, political and methodological challenges that require further studies and research

European Handbook of Crowdsourced Geographic Information

"This book focuses on the study of the remarkable new source of geographic information that has become available in the form of user-generated content accessible over the Internet through mobile and Web applications. The exploitation, integration and application of these sources, termed volunteered geographic information (VGI) or crowdsourced geographic information (CGI), offer scientists an unprecedented opportunity to conduct research on a variety of topics at multiple scales and for diversified objectives. The Handbook is organized in five parts, addressing the fundamental questions: What motivates citizens to provide such information in the public domain, and what factors govern/predict its validity?What methods might be used to validate such information? Can VGI be framed within the larger domain of sensor networks, in which inert and static sensors are replaced or combined by intelligent and mobile humans equipped with sensing devices? What limitations are imposed on VGI by differential access to broadband Internet, mobile phones, and other communication technologies, and by concerns over privacy? How do VGI and crowdsourcing enable innovation applications to benefit human society? Chapters examine how crowdsourcing techniques and methods, and the VGI phenomenon, have motivated a multidisciplinary research community to identify both fields of applications and quality criteria depending on the use of VGI. Besides harvesting tools and storage of these data, research has paid remarkable attention to these information resources, in an age when information and participation is one of the most important drivers of development. The collection opens questions and points to new research directions in addition to the findings that each of the authors demonstrates. Despite rapid progress in VGI research, this Handbook also shows that there are technical, social, political and methodological challenges that require further studies and research.

Scalable Methods to Collect and Visualize Sidewalk Accessibility Data for People with Mobility Impairments

Poorly maintained sidewalks pose considerable accessibility challenges for people with mobility impairments. Despite comprehensive civil rights legislation of Americans with Disabilities Act, many city streets and sidewalks in the U.S. remain inaccessible. The problem is not just that sidewalk accessibility fundamentally affects where and how people travel in cities, but also that there are few, if any, mechanisms to determine accessible areas of a city a priori. To address this problem, my Ph.D. dissertation introduces and evaluates new scalable methods for collecting data about street-level accessibility using a combination of crowdsourcing, automated methods, and Google Street View (GSV). My dissertation has four research threads. First, we conduct a formative interview study to establish a better understanding of how people with mobility impairments currently assess accessibility in the built environment and the role of emerging location-based technologies therein. The study uncovers the existing methods for assessing accessibility of physical environment and identify useful features of future assistive technologies. Second, we develop and evaluate scalable crowdsourced accessibility data collection methods. We show that paid crowd workers recruited from an online labor marketplace can find and label accessibility attributes in GSV with accuracy of 81%. This accuracy improves to 93% with quality control mechanisms such as majority vote. Third, we design a system that combines crowdsourcing and automated methods to increase data collection efficiency. Our work shows that by combining crowdsourcing and automated methods, we can increase data collection efficiency by 13% without sacrificing accuracy. Fourth, we develop and deploy a web tool that lets volunteers to help us collect the street-level accessibility data from Washington, D.C. As of writing this dissertation, we have collected the accessibility data from 20% of the streets in D.C. We conduct a preliminary evaluation on how the said web tool is used. Finally, we implement proof-of-concept accessibility-aware applications with accessibility data collected with the help of volunteers. My dissertation contributes to the accessibility, computer science, and HCI communities by: (i) extending the knowledge of how people with mobility impairments interact with technology to navigate in cities; (ii) introducing the first work that demonstrates that GSV is a viable source for learning about the accessibility of the physical world; (iii) introducing the first method that combines crowdsourcing and automated methods to remotely collect accessibility information; (iv) deploying interactive web tools that allow volunteers to help populate the largest dataset about street-level accessibility of the world; and (v) demonstrating accessibility-aware applications that empower people with mobility impairments

Sculpting reality from our dreams: Prefigurative design for civic engagement

At their core, organizing and activist work are about envisioning and working towards an alternative, more just political future. Various digital tools are used to support activist work, however these tools engage with values that are at odds with activist practices: where many activists do work in the service of social justice and equity, the digital tools they use are often corporate made, and thus support the status quo, i.e. profit generation, cis-heteropatriarchy, white supremacy, oppression. The ideals underlying activists’ equitable visions—of a more accessible and just future—drive their practices. This intentional alignment falls under the purview of prefigurative politics, where political work “express[es] the political ‘ends’ of their actions through their ‘means.’” [53] If activists envision a more democratic future, they adopt more equitable practices in the present in anticipation of building a more equitable future. This dissertation explores the role of digital tools to contribute to—to prefigure—alternative, more radical political values. My work uses design research and anarchist literature to explore the opportunities that ICTs offer in support of radically progressive political organizing. This work offers prefigurative design as an approach for designers and practitioners who work with communities in service of progressive political change. Prefigurative design is an orientation within HCI design and research that encourages critical reflection of research and design practices to better align design artifacts and processes with anarchist goals of anti-oppression and collective liberation, ultimately building counter-structures to replace existing institutions complicit in violence and oppression.Ph.D