® Sponsored by Volunteered Geographic Information (VGI) Workshop 96th OGC Technical Committee Nottingham, UK 14 September 2015 Copyright © 2015 Open Geospatial Consortium

OGC ® Agenda 1.Introduction to VGI content and methods –discussion of the common VGI data sources, methods of collection, licensing terms, COBWEB examples 2.Relevance of Standards to the VGI community –where standards can contribute: data exchange, data quality, data service and user interfaces –other requirements that can be standardized: ontology, semantics, portrayal/symbology 3.Challenges for VGI data exchange - role of standards –VGI community concerns with restricting flexibility in content –dissemination requires rules: how to GeoPackage something like Open Street Map? –COBWEB O&M citizen profile –Sensors and sensor webs 4.Challenges for VGI data quality assessment - role of standards –implications for data fusion and propagation of uncertainty –Provenance –precision and lack of consistency for any single source –accuracy vs. completeness 5.Summary and Actions –focus on next steps for OGC: new Domain Working Group (DWG)? Introduce topics into existing DWGs? Whitepaper mapping Standards to problems? Copyright © 2015 Open Geospatial Consortium

OGC ® Introduction and goals Purpose: to discuss the nature of VGI and issues with respect to data discovery, quality, and sharing Goals: map next steps for OGC… new DWG, Whitepaper? Copyright © 2015 Open Geospatial Consortium

OGC ® How this will work Quick touch on many topics Some deeper exploration of a few to provide examples of the intersection between VGI and Standards Finish with discussion of issues (feel free to disagree) and identification of next steps Copyright © 2015 Open Geospatial Consortium

OGC ® INTRODUCTION TO VGI CONTENT AND METHODS Copyright © 2015 Open Geospatial Consortium

OGC ® Common VGI datasets OpenStreetMap –Public participation –No formal quality control –Automation in quality assurance USGS National Map Corps CrisisMappers WikiMapia And specialty datasets –Mountain Project –MTB Project Copyright © 2015 Open Geospatial Consortium

OGC ® Collection/aggregation methods Web portal –Digitize in portal against reference info (typically imagery) –Upload GPS “tracks” or points Machine aggregator –Scour public or free data –Rule-based conflation (fusion) Copyright © 2015 Open Geospatial Consortium

OGC ® Licensing issues and non-issues This could take all day… License terms range from non-existent to “attribution only” to no commercial reuse to very restrictive Working with one license for one data set is complicated enough… but combining data and license terms is a legal struggle Re-publishers are worried about copyright infringement But many (most?) terms are reasonable and not intended to restrict use of the data Copyright © 2015 Open Geospatial Consortium

OGC ® Example: COBWEB Copyright © 2015 Open Geospatial Consortium

OGC ® Discussion Attendees: what do you think of when you think of VGI? Do you use VGI now? Do you contribute to VGI now? Copyright © 2015 Open Geospatial Consortium

OGC ® RELEVANCE OF STANDARDS TO THE VGI COMMUNITY Copyright © 2015 Open Geospatial Consortium

OGC ® Data exchange Standards enable… –data exchange: fits the VGI “ethos” –compilation of diverse content –distribution of VGI collection efforts to multiple instantiations for later combination Copyright © 2015 Open Geospatial Consortium

OGC ® Data quality Standard data formats and services remove one obstacle for making comparisons of quality between datasets Common methods for describing quality enable users to evaluate whether content is fit for their use Copyright © 2015 Open Geospatial Consortium vs.

OGC ® Data services Online access to data in common service formats increases uptake of the data Standardized services enable data fusion and cross- content analysis Web processing services work with standardized sources Copyright © 2015 Open Geospatial Consortium

OGC ® What else can be standardized? Ontology Semantics Portrayal/symbology Copyright © 2015 Open Geospatial Consortium

OGC ® Discussion We may be “preaching to the choir” – while standards might be relevant, are they critical? Let’s keep this discussion short, as we will examine the place for standards in VGI in more detail in the next two parts of this workshop Copyright © 2015 Open Geospatial Consortium

OGC ® CHALLENGES FOR VGI DATA EXCHANGE - ROLE OF STANDARDS Copyright © 2015 Open Geospatial Consortium

OGC ® VGI community concerns about standards Standards can be overly-restrictive and limit content and participation Standards can be difficult to implement VGI by its nature is very dynamic – can traditional schemas keep up? Are there good transactional data repositories and services? The Standards community is dominated by large corporations and governments… “the man is keeping me down” Copyright © 2015 Open Geospatial Consortium

OGC ® Dissemination and integration requires rules Any single dataset with a completely unrestricted schema in its own format is valuable only by itself Combining multiple datasets greatly increases their utility: one of those “1 + 1 = 3” things At a minimum, VGI holdings should have Standardized metadata to describe the content and format Better: VGI holdings are available via a Standardized web service Best: VGI holdings enforce some rules on geometrical constructs and attributes Copyright © 2015 Open Geospatial Consortium

OGC ® Discussion Are VGI community concerns well-founded? Should the burden of data integration fall upon integrators, not creators? Copyright © 2015 Open Geospatial Consortium

OGC ® CHALLENGES FOR VGI DATA QUALITY ASSESSMENT - ROLE OF STANDARDS Copyright © 2015 Open Geospatial Consortium

OGC ® Didier Leibovici, Sam Meek, Julian Rosser & Mike Jackson University of Nottingham Outline: –VGI data quality model (data captured and citizen capturing) –Provenance: citizens & data curation process (including the QAQC) –Metaquality –Single data quality assessment vs dataset quality ‘aggregation’ –Implications for data fusion and propagation of uncertainty Copyright © 2015 Open Geospatial Consortium Challenges for VGI data quality assessment - role of standards

OGC ® Challenges for VGI data quality assessment - role of standards facts: –Variation in the capturing device i.e., (User(s)) impacting data collected –accuracy vs completeness, e.g., OSM, biodiversity –precision but lack of consistencye.g., different ontologies –Different types of crowdsourcing.citizen science, VGI, passive crowdsourcing) –VGI used to ‘validate’ authoritative data vs authoritative data helps to quality assure VGI –Other facts? Copyright © 2015 Open Geospatial Consortium

OGC ® 1) VGI data quality model (data captured and citizen capturing) Spatial data quality: producer model ISO19157 consumer/feedback model (see GeoViQUA) But with VGI such as citizen science - variations between users and within users - role of the ‘carried’ and ‘enabing’ device e.g., design of the app human device + instrument(s) device used by the human needs: –Qualifying ‘users’ along with ‘single/series’ data Copyright © 2015 Open Geospatial Consortium

OGC ® Quality models and QAQC Copyright © 2015 Open Geospatial Consortium DQ_ xxx producer model ISO19157 GVQ_xxx consumer model User Feedback (GeoviQua) CSQ_xxx qualifying the user COBWEB StakeHolder Quality model A single QC QAQC= Quality Assurance Quality Control

OGC ® CSQ_xxx qualifying the user COBWEB StakeHolder Quality model Copyright © 2015 Open Geospatial Consortium A single QC

OGC ® 2) Provenance: citizens & data curation process (including the QAQC) Metadata on the survey / crowdsourcing set up citizen data profile QAQC  Quality Information and Quality assessment method on data captured/users capturing Provenance model W3C, link with metaquality needs: –Flexible ways of ‘understanding’ the QAQC –citizen data profile (see O&M and Bart’s presentation) Copyright © 2015 Open Geospatial Consortium

OGC ®.QA workflow Authoring Tool BPMN encoding.QA workflow Ontology Semantic support SKOS encoding.running WPS, workflow engine The QA workflow is composed of more than one QC into a workflow that may loop back /feedback to the user or to other users etc. to get additional information. (confirmatory / ensemble / linked data ) Flexible QAQC process with authoring tool and WPS calls QAwAT QAwOnt QAwWPS See also Sam’s presentation in WPS SWG

OGC ® QA workflow Ontology (top classes) the 7 pillars Meek, S Jackson, M Leibovici, DG (2014) ) A flexible framework for assessing the quality of crowdsourced data.AGILE conference, 3-6 June 2014, Castellón, Spain

OGC ®

® example Copyright © 2015 Open Geospatial Consortium A flooding data capture QA workflow Qualifying the observations, the users and the authoritative data Quality elements -Obs /Auth - ISO19157 standard -Auth - GeoViQUA-feedback model -User -COBWEB-Stakeholder Quality Model

OGC ® 3) Single data quality assessment vs dataset quality ‘aggregation Metaquality - across 2) Provenance… and 3) metadata information on the quality assessment method QAQC is taylored at single data capture (initialy) - derivation of dataset level quaity from qualities over the same user and/or collection of users Fit for purpose / usability –Combination of the three quality models to ‘make one’s mind’ on usefulness or GeoViQUA and COBWEB Stakeholder omdel only to weight things up for ISO19157? needs: –Metaquality & provenance (also at single data level!) –Methods for aggregating / fusing single data qualities to datasets Copyright © 2015 Open Geospatial Consortium

OGC ® 4) Implications for data fusion and propagation of uncertainty Facts on the approach: –propagation of uncertainty within the QAQC –Error propagation using VGI data (idem as with other data but desirefor for ‘regular’ updates) In 3) this is already a fusion ‘of the qualities’ For fusion of various data sources and VGI data sources –Machine readable/usable range of information on quality needs: –Machine readable provenance (to be used for data fusion) –Methods for aggregating / fusing single data qualities to datasets –Organising data & metadata at multiple levels Copyright © 2015 Open Geospatial Consortium

OGC ® Challenges for VGI data quality assessment - role of standards Copyright © 2015 Open Geospatial Consortium needs: –Qualifying ‘users’ along with ‘single/series’ data –Flexible ways of understanding the QAQC –citizen data profile (see O&M and Bart’s presentation) –Metaquality & provenance (also at single data level!) –Machine readable provenance (to be used for data fusion) –Methods for aggregating / fusing single data qualities to datasets –Organising data & metadata at multiple levels

OGC ® Discussion Will standardized descriptions of quality give you confidence in your use of VGI? Does the cost to evaluate quality result in a return of value? Copyright © 2015 Open Geospatial Consortium

OGC ® SUMMARY AND ACTIONS Copyright © 2015 Open Geospatial Consortium

OGC ® Next steps Do we need a DWG? Should there be a concerted effort to prepare VGI topics for discussion in other DWGs? Write a white paper for consumption by the VGI industry OGC staff provide outreach to VGI community Copyright © 2015 Open Geospatial Consortium