Vyron (Byron) Antoniou

WG5 Deliverable 1 – Citizen-science ontology. A WG5's specific objective was to help develop an ontology of citizen-science projects (including a vocabulary of concepts and metadata) to support data sharing among citizen-science projects. WG5 coordinated with activities on data and service interoperability carried out in Europe, Australia and the USA (e.g., the CSA's international Data and Metadata Working Group [http://www.citizenscience.org/association/about/working-groups/data-and-metadata-working-group/]), and took into account existing standards.

Volunteered geographic information (VGI) eloquently sums a wide variety of activities that generate geospatial content. While this content has taken many forms this chapter focuses on data sets that are used in the context of geographical citizen science projects. Citizen science covers a wide range of activities which in essence empowers communities to act on available or newly gathered data. However, there are issues of concern when it comes to the volunteers’ capacity to support a sustainable flow of appropriate data. In this context, this chapter immerses into one of the major factors that play a crucial role in the development of geographical citizen science: data quality. We first discuss the characteristics of VGI and then use this experience on citizen science project that has as a basic component the collection of geographic information. We present the quality challenges that such projects can face, and we discuss in a step-by-step mode best practices that can enhance data quality.

The appearance of OpenStreetMap (OSM) in 2004 sparked a phenomenon known as Volunteered Geographic Information (VGI). Today, VGI comes in many flavours (e.g. toponyms, GPS tracks, geo-tagged photos, micro-blogging or complete topographic maps) and from various sources. One subject that has attracted research interest from the early days of VGI is how good such datasets are and how to combine them with authoritative datasets. To this end, the paper explores three intertwined subjects from a quality point of view First, we examine the topo-semantic consistency of OSM data by evaluating a number of rules between polygonal and linear features and then paying special attention to quality of Points of Interest (POIs). A number of topo-semantic rules will be used to evaluate the valididy of features’ location. The focus then turns to the use of geo-tagged photos to evaluate the location and type of OSM data and to disambiguate topological issues that arise when different OSM layers overlap.

This paper presents an end-to-end methodology that can be used in the disaster response process. The core element of the proposed method is a deep learning process which enables a helicopter landing site analysis through the identification of soccer fields. The method trains a deep learning autoencoder with the help of volunteered geographic information and satellite images. The process is mostly automated, it was developed to be applied in a time- and resource-constrained environment and keeps the human factor in the loop in order to control the final decisions. We show that through this process the cognitive load (CL) for an expert image analyst will be reduced by 70%, while the process will successfully identify 85.6% of the potential landing sites. We conclude that the suggested methodology can be used as part of a disaster response process.

Transmitting vector data over the Web is a challenging issue. Existing methods for vector delivery over the Web focus on progressive transmission techniques. Long standing problems in the formalization of dynamic generalization and the time needed for complex algorithms does not allow their implementation in real life applications. We propose a new method for data transmission over the Web based on tiles. We show that in client-server architecture the coordination of all involved parts can create an efficient way to transmit ...

Transmitting vector data over the Web is a challenging issue. Existing methods for vector delivery over the Web focus on progressive transmission techniques. Long standing problems in the formalization of dynamic generalization and the time needed for complex algorithms does not allow their implementation in real life applications. We propose a new method for data transmission over the Web based on tiles. We show that in client-server architecture the coordination of all involved parts can create an efficient way to transmit ...

Since the World Wide Web became a medium to serve spatial information there have been different methods to deliver a map over the Web. These methods vary from a trivial use of HTML‟s element to highly complex and sophisticated ones like distributed GIS services. Three of these methods are going to be briefly discussed due to their roles in the formation of Web mapping and Web GIS knowledge domain. These approaches are: (i) a methodology, followed by major commercial vendors, which rely on on-the-fly generation of raster maps on the server; (ii) an architecture proposed by OGC, a leading international organization, and introduces the concept of Web mapping services; and (iii) a solution based on popular APIs from companies like Google, Microsoft and Yahoo, that is considered as a start of a new era in Web mapping. While these solutions have managed to deliver spatial content to the users, they are heavily based on the pre-rendering of spatial information in a raster format. Such a strategy, though, bears a number of limitations. Limitations such as content inflexibility, limited interactivity and animation, limited functionality in the applications, non-conformance to a bi-directional Web, make this strategy not fitfor-purpose when it comes to special applications and visualization of XML-based data. This will be examined in order to justify the need for vector data on the client. While there is a growing need of vector encoding on the client, the fact remains that still there has not been a widespread acceptance and progress of mapping applications that use SVG though there are alternatives through hybrid mapping applications. A number of limitations are associated with vectors that range from intrinsic characteristics of the encoding to corporate decisions that should provide a focus for scholars and developers. The size of the XML-based files, the difficulties in holistically determining and modelling the cartographic process of generalization and unresolved issues related to efficient progressive transmission of vector data are major drawbacks. Moreover, the open structure of XML encoding raises intellectual property protection and rights management issues when serving spatial information. Finally, the denial of native support from IE, the predominant web browser, and the discontinuity in development from Adobe of the most popular plug-in deters the adoption of SVG. In the context of the aforementioned theoretical background a series of real world examples is examined. Vendor APIs of mapping applications are examined and the role of SVG in these is evaluated. Additionally, the effort to build task oriented applications like routing services (from vendors like Google, Yahoo and Microsoft) using SVG is discussed. Also, the realisation of bi-directional Web applications and the rise of volunteered geographic information is examined using wikimapia.org as a paradigm. Finally, a case study of delivering legislation, planning and building regulation information with the help of a WebGIS will be presented. This application was built using PostgreSQL (with PostGIS) as the spatial database and SVG to deliver maps. After the first wave of enthusiasm for the new mapping era based on popular APIs that led to the boom of mash-ups, the need for the next step in the evolution of Web mapping applications has emerged. It is clear that a raster only solution, though capable of providing an overwhelming amount of information, has a number of limitations due to the nature of raster files and thus vector overlays are needed to cover these limitations. In an effort to determine the most promising way for further research in vector transmission, a set of preliminary tests were undertaken in order to evaluate the efficiency of a hybrid mapping application using SVG, AJAX and the Google Maps API. These experiments show the inadequacy of Google Maps API to provide ways for efficient transmission of vector data. On the contrary, the use of Google Maps as a backdrop overlaid with spatial data encoded in SVG proves to be considerably more dynamic and efficient solution. Moreover, in these examples a new approach for the use of AJAX techniques in the transmission process of vector data is introduced that takes advantage of the particularities of SVG grammar. The characteristic of this method is the minimization of network latency and thus smooth rendering of vector data on the client without delays or "loading..." messages.

SUMMARY The role of XML technologies in GIS and Cartography becomes more and more critical offering great advantages in web-based applications. The objective of this study is to elaborate on the utilization of the XML specifications used in modern web cartographic ...

The appearance of OpenStreetMap (OSM) in 2004 sparked a phenomenon known as Volunteered Geographic Information (VGI). Today, VGI comes in many flavours (e.g. toponyms, GPS tracks, geo-tagged photos, micro-blogging or complete topographic maps) and from various sources. One subject that has attracted research interest from the early days of VGI is how good such datasets are and how to combine them with authoritative datasets. To this end, the paper explores three intertwined subjects from a quality point of view First, we examine the topo-semantic consistency of OSM data by evaluating a number of rules between polygonal and linear features and then paying special attention to quality of Points of Interest (POIs). A number of topo-semantic rules will be used to evaluate the valididy of features’ location. The focus then turns to the use of geo-tagged photos to evaluate the location and type of OSM data and to disambiguate topological issues that arise when different OSM layers overlap.

The acceptance of volunteered geographic information (VGI) as a valued and useful source of information for governments is growing at all levels. The aim of this report is to review governmental projects that incorporate voluntary and crowd-sourced data collection and to provide information that can be used to support the wider adoption of VGI (the terms crowd-sourced information and VGI are used interchangeably). To this end, the report compiles and distributes lessons learned and successful models from existing efforts by governments at different sectors and scales. This report explores different aspects of government use of VGI, including the maintenance of public space (streets, public buildings, and parks), education, health, tourism, and civil safety. It includes a set of case studies with a common structure, which are presented at the end of the report. This report provides background on the use of geographical information by government, which has a long history and should be...

In a seminal paper published in 2007, Mike Goodchild coined the term Volunteered Geographic Information (VGI) in an effort to describe ‘the widespread engagement of large numbers of private citizens, often with little in the way of formal qualifications, in the creation of geographic information’ (Goodchild, 2007: 217). At that point, rudimentary crowdsourced Geographic Information (GI) was created and disseminated freely with the help of innovative desktop applications (e.g. Google Earth) or web-based platforms (e.g. Wikimapia, OpenStreetMap). By crowdsourcing we refer to the action of multiple participants (sometimes thousands or even millions) in the generation of geographical information, when these participants are external to the organization that manages the information and are not formally employed by it. Since then a lot has changed and VGI now has a deep and broad agenda that ranges from implicitly contributed GI through social networks to rigorously-monitored citizen scie...

Despite the considerable growth in Volunteered Geographic Information (VGI) activities in citizen sensing and the evident opportunities for VGI use in map revision and updating, few European National Mapping Agencies (NMAs) or other types of government bodies have engaged significantly with VGI. Moreover, the level of engagement of NMAs with the VGI community varies greatly, and most of them have proposed their own tools for encouraging citizens and public partners to collect feedback or new data. There are numerous barriers limiting the participation of citizens and public partners in NMA data collection, including data quality issues, the motivation of the contributors and legal issues. The aim of this chapter is to give an overview of the experiences of some European NMAs in engaging with VGI. Guidelines and recommendations to support wider engagement with the VGI community are also proposed to help NMAs and interested government bodies exploit the potential of VGI for authoritat...

Since the World Wide Web (Web) became a medium to serve information, its impact on geographic information has been constantly growing. Today the evolution of the bi-directional Web 2.0 has created the phenomenon of User Generated Spatial Content. In this Thesis the focus is into analysing different aspects of this phenomenon from the perspective of a mapping agency and also developing methodologies for meeting the challenges revealed. In this context two empirical studies are conducted. The first examines the spatial dimension of the popular Web 2.0 photo-sharing websites like Flickr, Panoramio, Picasa Web and Geograph, mainly investigating whether such Web applications can serve as sources of spatial content. The findings show that only Web applications that urge users to interact directly with spatial entities can serve as universal sources of spatial content. The second study looks into data quality issues of the OpenStreetMap, a popular wiki-based Web mapping application. Here t...

A big leap in the agricultural sector is expected thanks to the operational deployment of Copernicus data and services, the new Earth Observation program of the European Commission. The huge quantity of data delivered freely along with the good level of resolution (spatial, temporal and spectral) will open up new opportunities for achieving the well-known sustainability of agriculture. At the same time, the new trends of crowdsourcing and citizen science are delivering a great deal of geographical data collected by ordinary users with a bottom-up process. The two type of data and their integration will be the base for the future application in the agricultural sector, albeit management of big geospatial dataset and quality of user generated data are issues to be addressed.

This chapter introduce the concept of Volunteered Geographic Information (VGI) within practices of mapping and cartography. Our aim is to provide an accessible overview of the area, which has grown rapidly in the past decade, but first we define what we mean by VGI.

Uncertainty over the data quality of Volunteered Geographic Information (VGI) is the largest barrier to the use of this data source by National Mapping Agencies (NMAs) and other government bodies. A considerable body of literature exists that has examined the quality of VGI as well as proposed methods for quality assessment. The purpose of this chapter is to review current data quality indicators for geographic information as part of the ISO 19157 (2013) standard and how these have been used to evaluate the data quality of VGI in the past. These indicators include positional, thematic and temporal accuracy, completeness, logical consistency and usability. Additional indicators that have How to cite this book chapter: Fonte, C C, Antoniou, V, Bastin, L, Estima, J, Arsanjani, J J, Bayas, J-C L, See, L and Vatseva, R. 2017. Assessing VGI Data Quality. In: Foody, G, See, L, Fritz, S, Mooney, P, Olteanu-Raimond, A-M, Fonte, C C and Antoniou, V. (eds.) Mapping and the Citizen Sensor. Pp. ...

The ever-growing availability of Earth Observation (EO) data is demonstrating a wide range of potential applications in the realm of land management. On the other hand, large volumes of data need to be handled and analysed to extract meaningful information and Geomatics coupled with new approaches such as Artificial Intelligence (AI) and Machine Learning (AI) will play a pivotal role in the years to come. Training datasets need to be developed to use these new models and Volunteered Geographic Information can be one of the promising sources for EO processing. Among the various applications, agriculture may benefit from the large dataset availability and AI processing. However, several issues remain unsolved and further steps should be taken in the near future by researchers and policy makers.

This chapter studies the spatial behavior of contributors to OpenStreetMap and links it to gamification mechanisms which provide a solution to issues that arise with patterns of participation. More specifically, three issues are identified: (1) high productive contributors show little commitment to return and update geographic features they created, (2) the gap between the accumulated percentage of created features and the accumulated percentage of updated features is widening, (3) there is a significant contrast between areas of high and low mapping activity. Spatial allocation games are described as a subclass of location-based games suitable for addressing the participation issues. Based on an analysis of the geogames Geograph, Foursquare, Ingress, and Neocartographer we identify common design patterns for the allocation and deallocation of places. In addition, we show how to map the participation issues map onto the game design patterns. Results from an agent-based spatial simul...

The appearance of OpenStreetMap (OSM) in 2004 sparked a phenomenon known as Volunteered Geographic Information (VGI). Today, VGI comes in many flavours (e.g. toponyms, GPS tracks, geo-tagged photos, micro-blogging or complete topographic maps) and from various sources. One subject that has attracted research interest from the early days of VGI is how good such datasets are and how to combine them with authoritative datasets. To this end, the paper explores three intertwined subjects from a quality point of view First, we examine the topo-semantic consistency of OSM data by evaluating a number of rules between polygonal and linear features and then paying special attention to quality of Points of Interest (POIs). A number of topo-semantic rules will be used to evaluate the valididy of features' location. The focus then turns to the use of geo-tagged photos to evaluate the location and type of OSM data and to disambiguate topological issues that arise when different OSM layers overlap.

Highlights • Developments in information technology have a direct impact on the aims, goals and missions of different geographic citizen science projects, and create both challenges and opportunities. • Geographic citizen science decision makers should always invest time and effort to increase their own technological awareness. • It is imperative for technologies adopted to be interoperable with other technologies used for the project or collaborative projects and not work in their own silos. • Technology should be an enabling factor for all and not create biases among participants.

Volunteered geographic information (VGI) eloquently sums a wide variety of activities that generate geospatial content. While this content has taken many forms this chapter focuses on data sets that are used in the context of geographical citizen science projects. Citizen science covers a wide range of activities which in essence empowers communities to act on available or newly gathered data. However, there are issues of concern when it comes to the volunteers’ capacity to support a sustainable flow of appropriate data. In this context, this chapter immerses into one of the major factors that play a crucial role in the development of geographical citizen science: data quality. We first discuss the characteristics of VGI and then use this experience on citizen science project that has as a basic component the collection of geographic information. We present the quality challenges that such projects can face, and we discuss in a step-by-step mode best practices that can enhance data quality.

This book features contributions stemming from the activities of the ENERGIC (European Network Exploring Research into Geospatial Information Crowdsourcing: software and methodologies for harnessing geographic information from the crowd) scientific network. Researchers from 23 European countries participate in ENERGIC. It is funded as action IC1203 by the COST (Cooperation in Science and Technology) programme, which is a European framework supporting trans-national cooperation among scientists, engineers, and scholars across Europe.