Peter Mooney

Characteristics of Heavily Edited Objects in OpenStreetMap

This paper describes the results of an analysis of the OpenStreetMap (OSM) database for the United Kingdom (UK) and Ireland (correct to April 2011). 15, 640 OSM ways (polygons and polylines), resulting in 316, 949 unique versions of these objects, were extracted and analysed from the OSM database for the UK and Ireland. In our analysis we only considered “heavily edited” objects in OSM: objects which have been edited 15 or more times. Our results show that there is no strong relationship between increasing numbers of contributors to a given object and the number of tags (metadata) assigned to it. 87% of contributions/edits to these objects are performed by 11% of the total 4128 contributors. In 79% of edits additional spatial data (nodes) are added to objects. The results in this paper do not attempt to evaluate the OSM data as good/poor quality but rather informs potential consumers of OSM data that the data itself is changing over time. In developing a better understanding of the characteristics of “heavily edited” objects there may be opportunities to use historical analysis in working towards quality indicators for OSM in the future.

An evolutionary algorithm for multicriteria path optimization problems

For many years researchers and decision makers (DMs) faced with multicriteria shortest path problems (MSPPs) have resorted to reductions to the classical shortest path problem (SPP) by means of weighted linear combinations of the criteria. Algorithmic and approximation schemes are available to solve MSPPs but these approaches often display complexities prohibitive to their implementation on real‐world applications. This paper describes the development of an Evolutionary Algorithm (EA) approach to MSPPs on networks with multiple independent criteria. The EA approach is shown to sufficiently explore the underlying network space, generate large candidate path sets, and evolve high quality approximations to the optimal MSPP solution(s). Opportunities for early termination of the EA in time‐critical applications are also offered. Among the issues for further work is the integration of the EA as a tool within a GIS for path optimization.

Segmentation performance evaluation for object-based remotely sensed image analysis

The initial step in most object-based classification methodologies is the application of a segmentation algorithm to define objects. Modelling the human visual process of object segmentation is a challenging task. Many theories in cognitive psychology propose that the human visual system (HVS) initially segments scenes into areas of uniform visual properties or primitive objects. If an accurate primitive-object segmentation algorithm is ever to be realized, a procedure must be in place to evaluate potential solutions. The most commonly used strategy to evaluate segmentation quality is a comparison against ground truth captured by human interpretation. A cognitive experiment reveals that ground truth captured in such a manner is at a larger scale than the desired primitive-object scale. To overcome this difficulty we consider the possibility of evaluating segmentation quality in an unsupervised manner without ground truth. Two requirements for any method which attempts to perform segmentation evaluation in such a manner are proposed, and the importance of these is illustrated by the poor performance of a metric which fails to meet them both. A novel metric, known as the spatial unsupervised (SU) metric, which meets both the requirements is proposed. Results demonstrate the SU metric to be a more reliable metric of segmentation quality compared to existing methods.

Analysis of Interaction and Co‐editing Patterns amongst OpenStreetMap Contributors

OpenStreetMap (OSM) is a very well known and popular Volunteered Geographic Information (VGI) project on the Internet. In January 2013 OSM gained its one millionth registered member. Several studies have shown that only a small percentage of these registered members carry out the large majority of the mapping and map editing work. In this article we discuss results from a social-network based analysis of seven major cities in OSM in an effort to understand if there is quantitative evidence of interaction and collaboration between OSM members in these areas. Are OSM contributors working on their own to build OSM databases in these cities or is there evidence of collaboration between OSM contributors? We find that in many cases high frequent contributors (“senior mappers”) perform very large amounts of mapping work on their own but do interact (edit/update) contributions from lower frequency contributors.

Quality Assessment of the Contributed Land Use Information from OpenStreetMap Versus Authoritative Datasets

Land use (LU) maps are an important source of information in academia and for policy-makers describing the usage of land parcels. A large amount of effort and monetary resources are spent on mapping LU features over time and at local, regional, and global scales. Remote sensing images and signal processing techniques, as well as land surveying are the prime sources to map LU features. However, both data gathering approaches are financially expensive and time consuming. But recently, Web 2.0 technologies and the wide dissemination of GPS-enabled devices boosted public participation in collaborative mapping projects (CMPs). In this regard, the OpenStreetMap (OSM) project has been one of the most successful representatives, providing LU features. The main objective of this paper is to comparatively assess the accuracy of the contributed OSM-LU features in four German metropolitan areas versus the pan-European GMESUA dataset as a reference. Kappa index analysis along with per-class user’s and producers’ accuracies are used for accuracy assessment. The empirical findings suggest OSM as an alternative complementary source for extracting LU information whereas exceeding 50 % of the selected cities are mapped by mappers. Moreover, the results identify which land types preserve high/moderate/low accuracy across cities for urban LU mapping. The findings strength the potential of collaboratively collected LU features for providing temporal LU maps as well as updating/enriching existing inventories. Furthermore, such a collaborative approach can be used for collecting a global coverage of LU information specifically in countries in which temporal and monetary efforts could be minimized.

OpenStreetMap in GIScience: Experiences, Research, and Applications

This edited volume presents a collection of lessons learned with, and research conducted on, OpenStreetMap, the goal being to promote the projects integration. The respective chapters address a) state-of-the-art and cutting-edge approaches to data quality analysis in OpenStreetMap, b) investigations on understanding OpenStreetMap contributors and the nature of their contributions, c) identifying patterns of contributions and contributors, d) applications of OpenStreetMap in different domains, e) mining value-added knowledge and information from OpenStreetMap, f) limitations in the analysis OpenStreetMap data, and g) integrating OpenStreetMap with commercial and non-commercial datasets. The book offers an ideal opportunity to present and disseminate a number of cutting-edge developments and applications in the field of geography, spatial statistics, GIS, social science, and cartography.

Workshop Approach To Developing Objectives, Targets And Indicators For Use In Sea

Strategic Environmental Assessment (SEA) is the process through which the impacts of plans and programmes on the environment are assessed. Objectives, targets and indicators are the tools through which these environmental impacts can be measured. The same objectives, targets and indicators may be used for all planning levels but it is also necessary to identify additional plan specific ones. We used a workshop based approach to provide an interface between planners and environmental scientists and to give examples of objectives, targets and indicators for biodiversity, water, air and climatic factors, which could be used in SEA for national, regional and local plans. In addition, we highlight the need for careful consideration during the selection process of these variables which will result in a more rigorous and robust SEA. This is a challenging process but once completed will maximise resources and reduce the workload later in the SEA process.

The potential for using volunteered geographic information in pervasive health computing applications

Volunteered geographic information (VGI), or geospatial crowdsourcing, is where citizens (volunteers) contribute data and information about the earth and environment that is explicitly or implicitly georeferenced and then disseminated via collaborative projects such as OpenStreetMap or social media such as Flickr, Twitter, and Facebook. VGI popularity is due in no small part to citizens making use of consumer devices, such as smartphones, to collect increasingly precise locational information and other environmental information. In this paper we describe the potential for using VGI in pervasive health computing applications. Pervasive health computing strives to provide healthcare (services or information) to anyone, at anytime, and anywhere by removing constraints of time and location. We use the OpenStreetMap (OSM) project as a case–study of a very successful VGI project. We analyse the strengths of OSM, its current applicability to pervasive health computing, and if it is a sustainable option for use as a source of spatial information for pervasive computing technologies, particularly in areas where access to information on healthcare services is limited or difficult. The paper closes by summarizing the advantages and challenges of VGI integration into pervasive health computing and outlining some of the key issues where further cross-disciplinary research is required.

Campus Guidance System for International Conferences Based on OpenStreetMap

We present a web-based, multi-lingual, campus guidance system with emphasis on pedestrian navigation aimed at providing support for delegates attending International Conferences at the National University of Ireland Maynooth (NUIM) campus. A special campus guidance system could improve the logistics of the conference and potentially attract more delegates to the conference. The Cloudmade Web Map Lite API which uses OpenStreetMap has been used for creating this interface. The system generates shortest pedestrian paths using both outdoor pavements and indoor corridors between various buildings and points of interests (POI). For visual assistance in pedestrian navigation geotagged images are used along the path at certain points in the route, such as road intersections, when the user needs to get their orientation correct. The interface is currently available in both English and Chinese language.

An Introduction to OpenStreetMap in Geographic Information Science: Experiences, Research, and Applications

Recent years have seen new ways of collecting geographic information via the crowd rather than organizations. OpenStreetMap (OSM) is a prime example of this approach and has brought free access to a wealth of geographic information—for many parts of the world, for the first time. The strong growth in the last few years made more and more people consider it as a potential alternative to commercial or authoritative data. The increasing availability of ever-richer data sets of freely available geographic information led to strong interest of researchers and practitioners in the usability of this data—both its limitations and potential. Both the unconventional way the data is being produced as well as its richness and heterogeneity have led to a range of different research questions on how we can assess, mine, enrich, or just use this data in different domains and for a wide range of applications. While this book cannot present all types of research around OpenStreetMap or even the broader category of User Generated Content (UGC) or Volunteered Geographic Information (VGI), it attempts to provide an overview of the current state of the art by presenting some typical and recent examples of work in GIScience on OSM. This chapter provides an introduction to the scholarly work on OpenStreetMap and its current state and summarizes the contributions to this book.