Chaos Computer Club - archive feed

Keynote about this event: https://projects.alpaka.space/jhber19/talk/LTKJ8W/

Kann man empirischen Studien trauen oder nicht? Wie kann ich gute Studien von schlechten unterscheiden? Und was mache ich, wenn es zu einem Thema Studien mit gegensätzlichen Befunden gibt? Der Vortrag soll helfen, Antworten auf diese Fragen zu finden und empirische Studien besser zu verstehen. Empirischen Studien begegnet man nicht nur in Vorlesungen und Laboren, auch in den Nachrichten und in Diskussionen werden sie zitiert und oft als unumstößliche Wahrheit dargestellt. Andererseits gibt es ein großes Misstrauen gegenüber diesen Studien. Den Satz „Traue keiner Statistik die du nicht selbst gefälscht hast“ hat wohl jeder schon gehört und beim Congress im letzten Jahr hieß es mit Verweis auf psychologische und sozialwissenschaftliche Methoden „Science is broken“. Aber entspricht das wirklich der Wahrheit? Der Vortrag beschäftigt sich mit der Frage, was die Denkweise hinter empirischen Studien ist und wie man sie besser verstehen kann. Dabei sollen sowohl Grundlagen wie Wahrscheinlichkeiten, verschiedene statistische Testverfahren und Metaanlysen als auch Probleme wie p-Hacking und die Replikationskrise angesprochen werden. Ziel des Vortrags ist es, den Zuhörer*innen einen Eindruck davon zu vermitteln, was empirische Studien aussagen können und was nicht. Dabei liegt besonderes Augenmerk auf der Frage, ob und welchen empirischen Studien man trauen kann. Man benötigt keine Vorkenntnisse zum verfolgen des Vortrages. Als Beispiele werden aktuelle und klassische Studien aus der Psychologie benutzt. about this event: http://fahrplan.2019.hackumenta.de/hackumenta/talk/M8X9PD/

Eine grundlegende Einführung in die Programmierung paralleler Tasks auf Grafikkarten von NVIDIA. Was an Grafikkarten cool ist? Wer über das Alter hinaus ist, in dem man beim Gedanken an Grafikkarten einzig an Spiele und möglichst hohe FPS denkt, weiß sicherlich, dass Grafikkarten für etliche weitere Zwecke zum Einsatz kommen. Hier produzieren sie Cryptowährungen in Mining-Farmen, dort errechnen sie Hashes für alle möglichen Zeichenkombinationen, um auf Passwörter rückschließen zu können. Doch wie funktioniert das eigentlich? Wie kann ich meine Grafikkarte programmieren? Wieso nutzen die Programme auf meinem Rechner nicht alle die Grafikkarte, wenn sie doch von einem so beeindruckenden Leistungsplus profitieren könnten? Und wieso möchte ich bei NVIDIA-Grafikkarten eigentlich immer die mit möglichst vielen CUDA-Cores kaufen, obwohl ich keine Ahnung habe, was die tun. Dieser Talk beleuchtet anhand von NVIDIAs CUDA die genannten Fragestellungen, weist auf architekturbedingt Beachtenswertes hin und vermittelt, dass man seine CPU nicht wegwerfen sollte. Gekrönt wird der Vortrag von einem Blick auf Optimierungsstrategien, die in einem echten Codebeispiel Anwendung finden. about this event: http://fahrplan.2019.hackumenta.de/hackumenta/talk/FK73M3/

The opening of the hackumenta in Kassel, Germany will involve two different phases. First, the "hack-lab", for which the hack will be conducted, will be located at the Kassel University of Applied Sciences. Here hackers will get their first stab at developing their software and testing it with a real life example. Secondly, they will be able to conduct "open" experiments using the platform. This will allow the hackers to connect to the public to make their software even more open and free. Hackumenta will have up to 50,000 users The project is the brainchild of Andreas Krawitz and his team from the "Hackumenta" company. The company is a subsidiary of the German Software House of Technology, whose board members include Jurgen Neugebauer, chief executive of Google, Michael Schroeter, head of IBM Research Germany, Dr Ulrich Schäuble, chairman of the German Bundesministerium for Economic Affairs, Erich Honecker and the Chancellor of Bavaria, Horst Seehofer. about this event: http://fahrplan.2019.hackumenta.de/hackumenta/talk/HNFPVC/

about this event: https://c3voc.de

about this event: https://c3voc.de

about this event: https://c3voc.de

about this event: https://c3voc.de

about this event: https://c3voc.de

Ein kurzweiliger Vortrag über die Möglichkeiten von Webscraping mit Puppeteer about this event: https://c3voc.de

Der Vortrag erzählt die Geschichte von "media.ccc.de", dem Videoportal des Chaos Computer Clubs. Vor 12 Jahren waren erstmals die Videos von 'ftp.ccc.de' direkt im Browser sichtbar. Damals wusste noch niemand wozu, schließlich konnte man die Dateien "einfach" per FTP herunterladen. Zuerst wurden die Videos noch als FLV mit dem Flash-Player ausgespielt, doch irgendwann konnte auch der letzte relevante Browser HTML5. Heute unterstützt media Tonspuren in verschiedenen Sprachen, Untertitel und vieles mehr. Erzählt wird die Evolution der Architektur, von 'webgen' und DNS Round Robin bis zur Rails Anwendung mit HTTP Redirector. Die meisten Videos werden vom CCC Video Operation Center auf diversen Veranstaltungen aufgezeichnet und anschließend auf media publiziert. Wir reden über diese Verarbeitungskette und die API, das CDN Backend, sowie das Rails Frontend 'voctoweb'. Doch zur Geschichte von media gehören auch immer wieder kleine Anekdoten, wie der gescheiterte Versuch Torrents mit Web-Seeds anzubieten, oder die gesperrten Videos in der Apple-TV App. about this event: https://c3voc.de

Fabi berichtet von der neuen Stickmaschine im nbsp des Chaotikum. Ein Vortrag im Rahmen der Fünf-Minuten-Termine. Die Idee ist einfach: An jedem vierten Mittwoch des Monats nutzen wir das volle Haus zum Open Space / Chaostreff und jede Person, die möchte, kann kurz vorstellen, was auch immer ihr vorschwebt. about this event: https://chaotikum.org/blog/2019/09/24/5-min-termine9/

Leo berichtet über Operationsverstärker. Ein Vortrag im Rahmen der Fünf-Minuten-Termine. Die Idee ist einfach: An jedem vierten Mittwoch des Monats nutzen wir das volle Haus zum Open Space / Chaostreff und jede Person, die möchte, kann kurz vorstellen, was auch immer ihr vorschwebt. about this event: https://chaotikum.org/blog/2019/09/24/5-min-termine9/

Öffentliche Haushalte sind der in Zahlen gegossene Kern der Politik. Haushalte sind allerdings komplex und ihre bürokratische Darstellung ist schwer zu verstehen. In diesem Talk präsentiert Christian seine Anwendung “Unsere Gelder” die helfen soll, Haushaltsdaten zu verstehen. Aktuell kann man in den Medien viel über den Lübecker und den Bundeshaushalt lesen. Doch wie einfach ist es einen Haushalt zu verstehen? Bei diesem Talk wird das Projekt “unsere Gelder” mit anschaulicheren Visualisierungen und Vergleichsmöglichkeiten vorgestellt. Das Ziel ist es, mehr Bürgern zu ermöglichen sich zu informieren und sich zu beteiligen. Über einen Katalog sollen die Daten der Haushalte gesammelt werden um auf https://unsere-gelder.de dargestellt zu werden. Das Projekt ist Open Source und die erzeugten Daten werden als Open Data jedem zur Verfügung gestellt. about this event: https://chaotikum.org/blog/2019/09/16/unseregeldertalk/

In early 2019, Open Data Manchester teamed up with Stockport council, Disability Stockport and Age UK Stockport to crowdsource data around mobility and accessibility in the town centre. This talk will cover the mapping methodology, findings, difficulties and solutions, as well as suggesting ways in which we can better map for these communities, making the data collected for OSM more inclusive and accessible for all. In early 2019, Open Data Manchester partnered with Stockport Council on a project called ‘Mapping Mobility Stockport’, funded through the ODI Geospatial Fund. Working with Age UK and Disability Stockport, the project crowdsourced data about accessibility issues in Stockport, drawing on the lived experiences of people with mobility impairments to supplement data already available to the council. The municipal environment often includes barriers that exclude people with restricted mobility. These barriers may be the result of natural topography, historic planning, deterioration of the urban environment or planned and unplanned maintenance. Some of the barriers may not be known to the local authority. People with mobility impairments are on the frontline when it comes to negotiating these obstacles, and often have their own knowledge and strategies in negotiating and circumventing them. This is a resource that could be invaluable in helping others who face similar challenges, as well as helping local authorities identify where interventions need to be made. One of the aims of Mapping Mobility Stockport was to begin to map and find ways to continue to share these strategies. Using our Joy Diversion format as a basis, Open Data Manchester co-designed and ran a series of workshops with Age UK and Disability Stockport, which brought together different techniques and mobility strategies contained within the local community to enable people of all abilities to explore and map their environment. We used large, hi-resolution maps of Stockport to scribble on and sketch out routes, before taking to the streets to document, photograph and map the kind of things that these communities come up against on a daily basis. This information was then added to Stockport Council’s mapping system and Open Street Map, helping create a mobility map of Stockport. This talk will explore how we collected this data, sharing some of the findings and insights from the project, such as how what is useful for one disability can be problematic for another (such as tactile paving, which is useful for those with visual impairments but can be problematic for a wheelchair user). The talk will also explore the difficulties that arose out of this when categorising and tagging these features, and question whether more needs to be done in terms of mapping the streets and sidewalk. about this event: https://pretalx.com/sotm2019/talk/9FQVUT/

We map because we care to represent the world. Yet maps are never "true", they are shaped by their creators and their circumstances. Map-making is world-making: maps by different authors can give access to different worlds. So how can we make, share, and use maps that are created _by_ these worlds, and not just by a privileged few? How can vulnerable communities influence how they’re represented and affected by our maps? The popular view is that mapping the world is just an act of reflecting reality and reflecting nature. People rely on map-makers like us to show them the “true” spatial arrangement of the world. And yet, making a map also involves making assumptions, omissions, additions, and generalisations, and it feeds on our training, experiences, and personal perspectives as map-makers. A map is never really “true”, it is shaped by the hands of its creators, and it is always also a product of chance and its circumstances of making, sharing, and use. It can be said that map-making is world-making: maps shape our understanding of the world, and inform our actions in the world, and a map by a different author can give access to a different world. So how do we create a map of the world that is created _by_ the world, and not just by a privileged few? To fully appreciate the complexity of this challenge we need to extend our understanding of what counts as maps and mapping, and why. In order to understand our responsibility as map-makers, we need to become both _critical_ and _caring_ cartographers. This shift in perspectives and attitudes can help us understand better what can happen when our everyday mapping practice connects with real-world circumstances. It may also help us become more responsible as the volunteer workers of OSM. David and Martin will guide you through a careful and caring consideration of OSM based on personal experiences, and talk about the responsibilities we carry as we map and make the world during difficult times. For example, we may encounter circumstances where the OpenStreetMap approach to openness brings complications. Can the communities represented on the platform make decisions about how they’re being written about? Indigenous communities around the world regard their land as sacred and don’t want it to be mapped. Should we as a global community know when not to map? There are circumstances where the act of mapping itself can bring danger to the mapper. Do we have the right methods to assess such risks? What support can we offer those who take them? If we don’t, whose hand gets to shape the map instead? And what does all of this this mean for a do-ocracy, where decisions emerge slowly and can often contradict each other? Or to put it even more broadly, how can we diversify, democratise, denaturalise, and decolonise open mapping? Who cares, you ask? David and Martin have participated in the OSM ecosystem as mappers, researchers, and organisers, and have been involved in the Humanitarian OpenStreetMap Team and other global mapping initiatives. Based on their personal experiences they will introduce you to a careful and caring consideration of OpenStreetMap cartography, and talk about the responsibilities we carry as we map the world. They ask you to consider that maps are not _universal_, and that even in OpenStreetMap many different maps and mappings are possible. They propose that a better map may be a _pluriversal_ one, where many different perspectives can coexist. Can OpenStreetMap accommodate this? Which practices can help us produce maps that represent the world more equitably? More importantly, if we think that mapping can make a difference in a time of global precarity, inequalities, climate catastrophe, and mass extinction, then they ask _you_ to care. about this event: https://pretalx.com/sotm2019/talk/F9D8QG/

Lightning Talks Lightning Talks about this event: https://pretalx.com/sotm2019/talk/MYFAAH/

As one of the outreach activities in Japan, OpenDatathon which holds mapping party and Wikipedia editing event simultaneously, are regularly held. As a member of an Organizer group, I will introduce OpenDatathon case studies and consider their potential. In Japan, many OpenDatathon are held by various operators. It does the mapping party and editing of Wikipedia, other OpenData editing as one event. This contributes to the increase in opportunities to learn OpenData, the exchange of people involved in OpenData, and the increase of contributors. As a member of the group that organizes OpenDatathon, I will explain the purpose, effect, and spread of this initiative. The purpose of OpenDatathon's activities is different for each organizing group. Among the purposes, cases aimed at local information distribution are worth noting. It edits information on OSM and Wikipedia and uses it for the development of the local community. Because Civic Tech communities and local government organizations are often interested in it. For example, the library is collecting material about the history of the area. Writing on Wikipedia using them is important to them. The number of OpenDatathon hosted by the library is increasing. We also frequently support events organized by other organizations. That way, they can manage the event without having direct contact with OSM and Wikipedia experts. In addition, it is possible for people of various motivations to participate by incorporating the fun of walking around town. In order to edit OSM and Wikipedia, We are looking for historical or important topics in the local area. In addition, we may hold multiple events as a series of historical themes. We are planning a story in mapping, and creating a motivation for people to participate by incorporating a specific feature. As our future challenge, not only disseminate local information by themselves, they will organize hackathon by using the OSM geospatial database and the Wikipedia document data. We want to increase activities. The code and data are linked in an area-oriented. about this event: https://pretalx.com/sotm2019/talk/LBREW8/

Lightning Talks Lightning Talks about this event: https://pretalx.com/sotm2019/talk/XQUHP3/

In many regions of the world, a population’s access to essential services is unduly constrained by a lack of proper infrastructure. By performing accessibility analysis using OSM data, we can understand how route infrastructure impacts access to essential services and use that information to inform an intervention. This talk explores accessibility analysis performed to understand the impact of footbridge construction in eSwatini and introduces a python framework enabling users to perform similar analysis. Bridges over rivers are fundamental pieces of human infrastructure which enable safe crossings for the populations who use them. However, many rural regions of the world lack these critical bridges, and as a result, access to essential services is restricted for millions of people. In pursuit of tackling poverty caused by rural isolation, we have begun experimenting using remote analysis techniques to quantify bridge need and impact. To these ends, accessibility analyses using OSM and other data have proven to be extremely valuable. By comparing a population’s baseline accessibility to its access in scenarios such as a flood or post bridge construction, one can better understand the transportation dynamics of a region and even estimate the number of people that would be impacted with a bridge construction, for example. During the course of running various accessibility models, a python framework tebetebe was built around OSRM [Open Source Routing Machine] which simplifies the process of running different scenarios. This framework is built with footbridges in mind but is generalized so it may be applied to other applications. This talk explores the accessibility analysis process, its caveats and results achieved in the Kingdom of eSwatini. Finally, a walkthrough of the python framework tebetebe is given so that other users may perform similar analyses. about this event: https://pretalx.com/sotm2019/talk/7FBMMM/

Have you ever been lost inside a gigantic railway station? SNCF, the french railway company, is developing a pedestrian routing and navigation service to help travelers find their way inside and around railway stations. This talk exposes the challenges and how they have been addressed to provide a robust solution that can handle the great variety of data as well as routing through open spaces. SNCF, the french railway company, has been using OpenStreetMap to map railway stations for years. Since 2016, travelers can explore all 380 railway stations of the Greater Paris area through interactive maps deployed on their web site and on a mobile app. Browsing a map is good, but not good enough when you are lost inside a complex, multilevel, indoor (and/or outdoor) environment. It gets worse for someone in a wheelchair, elderly people, or anyone coming back from a family trip with more luggage than your hands could carry. What if we could bring pedestrian routing and navigation services to help travelers find their way inside and around railway stations? Could we do it using OSM data? This is the challenge SNCF has been trying to tackle for the past few months. Together with Jawg Maps and Carto’Cité, they held a detailed mapping campaign on 83 stations and developed a dedicated routing engine. This engine can seamlessly navigate indoors and outdoors, and achieves routing through open spaces such as pedestrian areas and station halls. This talk exposes the challenges we faced. It focuses on the data structure and the algorithmic strategies that have been defined to provide a robust navigation service, and its ability to handle the great diversity of railway stations. The talk also discusses how some parts of the data model originally designed for road navigation could be used for pedestrian routing – with some minor tweaks. If you thought mapping stairs was trivial, you would be surprised… about this event: https://pretalx.com/sotm2019/talk/AT9YPK/

The OpenStreetMap provides probably the most comprehensive digital path network for pedestrians, which had been largely unused in its actual depth of detail so far. Based on findings from the TERRAIN project, this talk will go into detail how this network can be used for roadside-aware pedestrian navigation efficiently, and what challenges and mappings problems occurred. Furthermore, specific needs of various person groups will also have to be considered facing variable data quality. People primarily move on sidewalks, but this is hardly taken into account in generally available routing solutions. The OpenStreetMap provides probably the most comprehensive digital path network for pedestrians, which had been largely unused in its actual depth of detail so far. Through an efficient and transparent topological extension of the path network, more accurate routes for pedestrians and other means of transportation can now be determined, revealing hitherto unnoticed mapping problems and an undesirable previous focus on automotive mobility. As part of the TERRAIN project, an exemplary publicly available navigation system for blind persons was developed that demonstrates the special challenges of human locomotion based on the OpenStreetMap. Challenges and robust solutions concerning data quality, micro-mapping and transition areas, regional OSM semantics versus mapper interpretations, and path bundling are presented. A large part of the footpaths in the OpenStreetMap are listed in the form of annotations as sidewalks. This well-proven procedure enables a low-maintenance, robust and high coverage of the footpath network. However, a presentation with many paths inevitably leads to contradictions due to path bundling, which requires a more elaborate micro mapping, which is often not noticed by mappers up to now, and can now be shown clearly. But also regional micro mapping can lead to unexpected complications in addition to the increased effort, since a multitude of connection problems can occur which have to be considered. In addition, there are a large number of requirement profiles for children, adults, the disabled or the elderly who travel on foot, in wheelchairs or on scooters. A deeper examination of the map data enables a finer specialisation in different areas of application, which also uncovers and challenges previously unused data treasures and requires special handling in the software. about this event: https://pretalx.com/sotm2019/talk/ARMCT7/

As of today we have OpenStreetMap but it doesn't fit all data and some data is not recommended for submission. We've got user reviews request in OsmAnd and Maps.Me and we would like to collaborate with OpenStreetMap community to create independent open platform for reviews. I would like to talk about how data could be stored and moderated and would like to explain how that data will be further integrated with OpenStreetMap and will be contributed back to OSM! One of the main contribution to OSM database itself will be justified places and details of places itself. I will explain how tools will validate License sanity and avoid Import problem to OSM i.e. how every edit will be administered by OSM-user. In the end we would like to have seamless OSM user experience integration and create open OSM-satellite project. *OpenPlaceReviews - A new way for local reviews* Open. Collaborative. Trustworthy. Openness - make all the reviews data open, so every project can access and contribute back. Community driven - build a community to make decision about moderation, data structure together. Decentralization - develop a decentralized system from the Day 1 to avoid scalability issues in the future. Trust - create tools to detect fraud, spam & keep all the data open to prevent any data manipulation. Monetization - make business subscriptions once the project is matured and spread the income between applications, authors, moderators and network operators. Further Description will be provided. Further Description will be provided. Further Description will be provided. about this event: https://pretalx.com/sotm2019/talk/LBGPCD/

Closing Session Closing Session about this event: https://pretalx.com/sotm2019/talk/SWAGX7/

<p>'Public Transport Navigation using OpenStreetMap by OsmAnd'</p> <p>The presentation describes stages of developing and starting of new feature of OsmAnd app.</p> <p>OsmAnd is the first among the large OSM apps that developed public transport support. Now we continue to improve this function further, add new modes of transport, and experiment with the settings.</p> <p>How we came to the idea of ​​public transport? In the presentation, we will explain why we use the PTv2 scheme, why this option is preferred, and how it works. In addition, in our report, we will consider the future support of GTFS.</p> <p>During the work we faced various difficulties, so we will explain what these difficulties were and how we tried to build at least something. We will also cover how OSM users can help us, and whether it is possible and how long it will take to improve the data.</p> <p>Lastly, we will present our results and plans, namely, what was our most significant success and how we want to build an editor for public transport..</p> <p>We launched the function at the beginning of the year, and throughout the year we tested it, supplemented it with new conditions for building a route and tried to take into account all possible conditions for building routes. Although the data in the OSM have not proved to be always correct, everything can be fixed by the community.</p> about this event: https://pretalx.com/sotm2019/talk/NWW7GF/

Osmose-QA is a Quality Assurance tool pointing issues on map, but also able to compare external data set to OpenStreetMap. First part is about the new support of MapCSS rules in Osmose-QA and the opportunity to share rules with JOSM and other tools. Second part is on integration of external data from Mapillary photography objects extracted by AI and from OpenData. It is also on the challenge to deals with lots of OpenData. At the beginning, Osmose-QA is a Quality Assurance tool pointing issues on map, but also able to compare external data set to OpenStreetMap. First talk part is about the new support of MapCSS rules in Osmose-QA. MapCSS language was primarily designed as way to style map objects, it look like the web styling language CSS. The base of MapCSS is to use selectors to filter objects. JOSM already use it for map styling and validator. This new implementation of MapCSS in Osmose-QA allows to write rules more easily. It also allow to reuse JOSM validator rules set. Next step would be to run Osmose rules in JOSM. It’s a great opportunity to share rules across tools and projects. But come the question on how to share and manage this rules while considering tools particularities. Second talk part is on external data comparison (aka conflation) with OpenStreetMap. It permits to point issues and evaluate the coverage, lastly it allows fixing and integration into OpenStreetMap. The more we wait, the more there is OpenData sets available. How Osmose-QA can try to addresses this issue of already too many OpenData set available. Beside OpenData from authorities we also have street objects extracted by Mapillary AI from street photography. Finally, what about the limit of the current model and how we may go further. about this event: https://pretalx.com/sotm2019/talk/JJKH8H/

Pic4Review now helps contributors to integrate open data properly in OpenStreetMap using street pictures validation. Discover the way it works and how this can help improve both OSM and open datasets. [Pic4Review](http://pic4review.pavie.info/) is a new editor to work on OpenStreetMap using open street-level pictures offered by Mapillary, OpenStreetCam and Wikimedia Commons. You can create thematic missions to work on a specific subject. The features are loaded in the tool, which automatically find available pictures around it, and offers a simple interface to answer questions and editing the features. At start, it was helping contributors adding details on existing objects, like accessibility of crossings, name of shops, levels of buildings... This offers a wide range of possibilities, and was already used by hundreds of contributors to edit around 100000 features worldwide. Now, it also offers to integrate open datasets into OpenStreetMap, the proper way. The complexity of integrating open data in OSM lies in the accuracy of these datasets : we should check if features are correctly located, and properly described. This can be done by surveying, or using freely available pictures of our streets. This is what Pic4Review offers to simplify : import your dataset, create a mission, and work in team to integrate the data which can be verified. This talk will present the problem of open data integration, the Pic4Review tool, and the process of using it for integrating open data. about this event: https://pretalx.com/sotm2019/talk/JGHWKY/

Norway has deployed OSM on a national level for journey planning and is taking initiatives to expand the user, and usage of OSM in Norway and abroad. Entur’s mission is to enable and increase the use of public transport in Norway. Entur operates the national registry for all public transport in Norway, collecting data from 60 public transportation operators. The registry contains data about 21,000 daily departures on 3,000 routes. This data is open and free of use for app and service developers. We would very much like to present our success story of using OSM data as the foundation for all interchanges and routing in our national journey planner (used in the app: Entur, and http://en-tur.no), and the surprisingly easy challenges we faced due to the quality of OSM data, and the way we solved the large scale challenges, such as missing roads around the country. Why we are going to continue to build on the usage of OSM, OpenTripPlanner and other open source platforms on a European wide base to create an ever-improving public transport information distribution. We are actively engaging with the Norwegian community to build relations, improve quality and mapping methods, even arranging beer meetups. We are of course providing all our data openly, making it easy for OSM to make good use of for example our national stop place database, or for our NeTEx based time table data to be used in innovative solutions. about this event: https://pretalx.com/sotm2019/talk/CXVMJ8/

OSM2World is an open-source renderer capable of creating rich 3D worlds from OpenStreetMap data. It is now available as a web application powered by WebGL. OpenStreetMap contains a wealth of data that can be used to build a 3D representation of our world. Some of it, such as buildings mapped using the [Simple 3D Buildings](https://wiki.openstreetmap.org/wiki/Simple_3D_Buildings) tagging convention, is intended primarily for 3D use cases. Other feature classes, such as roads and railways, urban infrastructure, or landuse information, aren't usually mapped with 3D in mind, but are nevertheless essential ingredients of a 3D world. In either case, unlocking the full potential of OSM data and converting it into a representation that's suitable for typical use cases in the domain of 3D rendering requires specialized software tools. [OSM2World](http://osm2world.org/) is one of these tools. Fully open source, it can be used to export 3D data for modelling software, animations, and games, as a library in other programs, and as an interactive map on the web. Until recently, however, the lack of a powerful 3d rendering solution for the web put constraints on the features available without a local installation of the software. Today, the WebGL standard allows real-time 3D rendering in all major browsers. A new web frontend for OSM2World builds on these capabilities to allow users to explore the world in 3D, based entirely on open data. This talk demonstrates the abilities of OSM2World and its new web frontend, showcases some impressive 3D mapping around the world, and briefly explores how the software works behind the scenes. about this event: https://pretalx.com/sotm2019/talk/V7QPGG/

Replacing the classics "Continue for about 200 m then turn left" by guidance instructions in more natural language automated from landmarks are still a research topic but aims to allow users to move with more confidence. The objective is to test it on an indoor/outdoor pedestrian route calculator. Anything that can be used as a landmark is extracted from OpenStreetMap, then categorized and classified to annotate the route: relevance, visibility, relative position… Replacing the classics "Continue for about 200 m then turn left" by instructions in more natural language with landmarks incorporation. It aims to allow users to move with more confidence in and around railways stations. Guidance instructions in more natural language automated from landmarks are still a research topic. Innovation & Research branch of SNCF, French National Railway Company, has delegate to Makina Corpus the task to implementation the state of the art in this field. The objective is to test it and then improve an indoor and outdoor pedestrian route calculator under development. Anything that can be used as a landmark is extracted from OpenStreetMap, then categorized and classified. The landmarks are evaluated to annotate the route: relevance, visibility, relative position.… The process have to deals with indoor and outdoor but also as points or large landmarks. We talk on subjects like evaluate how OpenStreetMap objects are suitable to be landmarks. We also expose how check for objects visibility based only on OpenStreetMap data, or how to allow landmark to be visible from outside a building or room depending on the outdoor or indoor status of the observer. The railway stations context has the particularity to require support of transition between indoor and outdoor. about this event: https://pretalx.com/sotm2019/talk/ZJYT7F/

OpenMapTiles is an open-source set of tools for processing OpenStreetMap data into vector maps, which can be produced in various coordinate systems. OpenMapTiles is an open-source set of tools for processing OpenStreetMap data into zoomable and web-compatible vector tiles, which are ready to use in OpenLayers, Mapbox GL, Leaflet, QGIS as well as mobile applications. This talk gives an overview of the OpenMapTiles tools to produce vector tiles in coordinate systems other than Mercator while keeping all the features, such as interactivity to create powerful region-specific applications. Today’s de-facto global standard is a Spherical Mercator projection because it preserves shape and angles. The entire world looks like a square, which makes it easy to work with on a computer. However, such a transformation causes several issues like distortion of sizes where places around the equator are visually smaller than those near poles. That’s why new global coordinate systems were developed. There are also many local coordinate systems with a long tradition. They perfectly fit the need to display a particular country/area in the most acceptable way. They are heavily used, especially by governments. OpenMapTiles can serve as a base map for displaying data in a different coordinate system or for view/print purposes. There is also a hosting service based on OpenMapTiles called MapTiler Cloud, which offers the same ability to be displayed in a different coordinate system than Mercator. about this event: https://pretalx.com/sotm2019/talk/RYPLFZ/

Satellite imagery has materially enhanced OpenStreetMap and improved editing and validation. In this talk we will talk about recent enhancements we've made to get even more information from satellite imagery. DigitalGlobe, now known as Maxar Technologies, has been providing two sources of imagery directly for OpenStreetMap (OSM) users for tracing and validating. Over the past couple years, we’ve received a lot of excellent feedback from OSM users and we are making a few changes to better serve OSM volunteers. Part of this presentation will address some of the common questions we are asked, address some of the common feedback, and dive into the upcoming changes to the services that we provide. We want to do this to clear up any confusion or future questions the community might have. We will further demonstrate how we have integrated Maxar imagery into the OpenStreetMap ecosystem. In both iD and JOSM, we have developed a custom plugin that connects to the commercial satellite imagery service and provides a carousel view of available imagery in the visual extent of the editor. Images are arranged temporally providing opportunities to compare areas against different time periods. The plugin also applies the metadata from the image as tags on the feature, including source:imagery, source:imagery:layerName, source:imagery:sensor, and source:imagery:date. Leveraging these services and applying the metadata of the imagery enhances the mapping experience, enriches OSM data, and improves the end-user benefits. about this event: https://pretalx.com/sotm2019/talk/TVSA9F/

This talk discusses different ways how to improve the search experience for domain-specific maps. No map comes without a facility to search for places. As a result quite a few open-source geocoders using OpenStreetMap data have been developed and have matured in the last years. Nominatim, Pelias, Photon, Carmen, there are many to choose from. They all have in common that they offer a general purpose search for addresses, places and, to a more limited extent, places of interest. OpenStreetMap has inspired the creation of many domain-specific maps. Be it maps for specific features like brew pubs, camping or power infrastructure or for activities like cycling, hiking or child entertainment. A general purpose search on these maps is often not satisfying. The special features might simply not be available in the generic geocoders. And when they exist, they do not get the prominence appropriate for the map. This talk explores ways to improve the search experience for such special-interest maps. We start with simple approaches to boost results using existing web APIs and then look into different ways for creating a small custom domain-specific search engine. We discuss advantages and disadvantages of the different approaches and show common pitfalls for implementations. Although some knowledge in system administration and programming is expected, the focus is on solutions for small and medium projects that are realized with limited resources. about this event: https://pretalx.com/sotm2019/talk/PJE8GK/

In this research, the OSM-Notes feature is mainly viewed as data that can be examined speedily from OSM data globally in terms of the content of the notes posted and the location of users. Data from volunteered geographic information (VGI) and public surveying are essentially different; while a great quality and quantity of data is available for VGIs, discussions about data quality are scarce (Senaratne et al., 2017). As the use of VGI in business expands, attempts have been made to develop quality verification tools (cf. KeepRight and Validation OSM) with the understanding that, in addition to position accuracy, data quality equally depends upon the diversity and interaction of the number of users involved in data generation (Haklay et al, 2010). OSM-Notes is a capability for describing errors and discussing OSM data and fixme, although there are few research cases (Seto et al., 2017). This feature is new and was only added to OSM.org in April 2013. It allows users to specify and comment on any point on the map, and the history of comments can be accumulated and closed when the problem is solved. Unlike the fixme tag (allows contributors to mark objects and places that need further attention in the form of a "note to self" or request for additional mapping resources), this function does not directly associate with OSM data, but there is no need to have an OSM account. In this research, the OSM-Notes feature is mainly viewed as data that can be examined speedily from OSM data globally in terms of the content of the notes posted and the location of users. The purpose of the research is to analyze the context of OSM-Notes use through a “GIS” approach (Cope & Elwood, 2009). This analysis was conducted on data dumped from Planet OSM (https://planet.openstreetmap.org/) as April 2019. Since planet-notes.osn (about 782MB) is a special binary format, we used an enhanced parser able to separately output open (unresolved discussions) and closed (resolved discussions) based on osn2osm. After converting to .osm format data, the set was combined with Natural Earth's border data and population data and treated as spatial data. As a result, there were OSM-Notes postings in 237 countries: 415,433 open and 129,887 closed records. By counting the number of OSM-Notes postings by country based on whether they are open or closed, we determined that the majority were in the United States, Germany, and Russia. Moreover, it became clear that Japan, Canada, Korea, and Taiwan are the regions where there are a large number of submissions in urban areas (based on Natural Earth’s definition). In addition to these, many OSM users have posted from many countries, including Iraq, Ukraine, and Ecuador, and it is clear that active discussions are being held by many contributors. In these countries, mapping for humanitarian assistance is commonplace, as other reference resources are unavailable, so it is necessary to improve data quality through the use of OSM-Notes. OSM-Notes even has a function that allows non-OSM users to post, as is the case with 50% or more of the posts in Spain, Korea, etc. This data can be used to analyze urban trends and spatial features within a single country. For example, according to the analysis for Japan, OSM-Notes has many posts about the location of shops and POI (Point of Interest), and suggestions based on Maps.ME, Facebook, and Pokémon go. This is considered to be the main reason that anonymous posting is permitted. It is also worth noting that very few users post only a single note. Thus, by analyzing OSM-Notes, it is possible to grasp hot issues between users of OSM data. Overall, OSM mapping was found to be more common in developed countries with active mapping, but similarly, bug reports from non-OSM applications as developing countries that require discussion among OSM users, and as a new aspect. Moreover, how to accept it is an important issue in considering the process of constructing OSM data. However, because the functional relationship between OSM-Notes and the data on OSM cannot be specified directly, the nature of the feature is also difficult to grasp directly compared to the fixme tag. about this event: https://pretalx.com/sotm2019-at/talk/GRR3N3/

JOSM is almost as old as OSM but few people really know what it takes to maintain your preferred editor. We'll present the development model of JOSM and who's part of its active community: developers, translators, testers, plugin authors, end users, sponsors, etc. We'll talk about the project difficulties, the major achievements made in the past years, what work is currently in progress and what will happen in the near future! JOSM is almost as old as OSM but few people really know what it takes to maintain your preferred editor. We'll present the development model of JOSM and who's part of its active community: developers, translators, testers, plugin authors, end users, sponsors, etc. We'll talk about the project difficulties, the major achievements made in the past years, what work is currently in progress and what will happen in the near future! about this event: https://pretalx.com/sotm2019/talk/88ZHKQ/

More than 17 million edits globally have been made by paid contributors in the last five years. We look at the long history of corporate involvement in OSM and then dig into the data to quantify the impact this latest evolution of corporate involvement is having on the map and explore the interactions between paid and volunteer mappers. OpenStreetMap (OSM) is both a map and the active community of over a million mappers that create and maintain it. Participation in OSM has largely been studied in terms of motivation and the resulting data quality. Today, the community is comprised by many different interest groups including craft/hobby mappers, humanitarian mappers, professional mappers, and more. The last few years have seen a dramatic growth in a specific group of mappers: corporate editors. These are mappers hired by corporations and edit the map as part of their employment. In November 2018, the OSM Foundation published the _organized editing guidelines_ that outline a number of steps all groups engaged in organized editing activities (including corporate data teams), should take to promote transparency, openness, and engagement with other mappers—especially local community. This work identifies ten corporations that are complying with these guidelines and explores their mapping activities. We found these corporations have cumulatively edited over 17M objects globally in the last five years, of which 9M were edited in 2018 [1]. First, we traced the history of corporate involvement in OSM to show that while this growing phenomena of corporate editing is new, it represents just the latest stage in a long history of corporations both contributing to and benefitting from OpenStreetMap. Next, we used historical quarterly-snapshot OSM-QA-Tiles to quantify where the ten corporations are active on the map and what types of edits they are performing. We find these edits are global in geographical scope, yet vary per corporation in location and edit type: Corporations heavily impact road networks, yet non-corporate mappers maintain the majority of all edits by mapping more buildings and points-of-interest [1]. To date, this research has quantified and contextualized the growing phenomena of corporate editing in OSM and identified the need for more in-depth analysis to more descriptively explain the impact to the map and volunteer mappers in these regions where corporate-editors are active. To further explore these impacts, we need to dig deeper into the editing record to describe the evolution of the map. For this, we are building upon open-source OSM data-processing tools to construct new vector tiles with with full OSM editing histories [4]. These new historical analysis tiles allow us to efficiently explore the evolution of the map in these regions. This allows us to better contextualize and visualize the interactions between corporate editors and volunteer mappers at scale. Previous research has shown that the road network typically gets mapped first and the map builds up from there [2]. To this extent, we will explore the notion of _map seeding_ whereby paid editors create the first version of the road network, seeding the map for others to maintain and grow. Supporting such an idea is the concept of _densification_ of the map, where some mappers prefer to edit where there is existing—though incomplete or sparse—map data, instead of a beginning with a blank section of map [3]. The concept of such editing patterns highlights the nuances in effectively measuring the impact of paid editing on the map. In other words, this question is more complicated than “are corporate editors taking over?” The first part of the research presented here was recently published [1]. The deeper exploration of the data to identify and explain the impact to the map and local communities is current, ongoing research. At State of the Map, I will briefly summarize the completed work to better set the context, and then present the results of our ongoing investigation on the impact to the map and community. 1. Anderson, J., Sarkar, D., & Palen, L. (2019). Corporate Editors in the Evolving Landscape of OpenStreetMap. ISPRS Int. J. Geo-Inf. 8, 232. 2. Ciepłuch, B., Mooney, P., & Winstanley, A. C. (2011). Building Generic Quality Indicators for OpenStreetMap. 19th Annual GIS Research UK (GISRUK), 5. Retrieved from http://eprints.maynoothuniversity.ie/2483/ 3. Corcoran, P., Mooney, P., & Bertolotto, M. (2013). Analysing the growth of OpenStreetMap networks. Spatial Statistics, 3, 21–32. https://doi.org/10.1016/j.spasta.2013.01.002 4. OSM-Wayback Utility available at https://github.com/osmlab/osm-wayback about this event: https://pretalx.com/sotm2019-at/talk/W8BA9K/

The OSM data model has facilitated rapid growth of community-created geodata which third parties can build on. But as more accuracy is needed in routing, cartography, and other uses, is this data model good enough? We are trying to represent spaces as flows, which result in fundamental compromises and inaccuracies. This talk will discuss real-world cases where this compromise is increasingly problematic. OpenStreetMap was designed to enable ordinary people to create open geodata that anyone can use and maintain easily. Traditional GIS concepts such as layers are dispensed with in order to make editing simple and accessible. In the same way that the web would never have taken off if HTML were not so accessible and tolerant of mistakes, this simplicity in OSM has meant a low barrier to involvement. However, as OSM is becoming more widely used in the mainstream, the need for accuracy and quality is becoming more and more important. Cyclists need detailed turn data to enable high-quality routing that takes full account of safety. Satnav companies, need lane data, which is difficult to represent accurately. Pedestrian routing is barely in its infancy and high quality routing for people walking or using wheelchairs is hard to achieve. At its root, OSM tries to represent spaces as flows (lines). This results in fundamental compromises and inaccuracies. What is good for routing is not always good for cartography, and vice-versa. For instance, a street containing cycleways with pavements either side is usually represented as a single line with attributes. However, it is extremely challenging to represent properly all the parts of the street, and in general people simply don't bother: a single line with large numbers of attributes is unwieldy to edit (even when hidden by editor GUIs), and just as challenging for a router to interpret. Continual changes in the width of a street cannot be easily represented without segmenting the street heavily and creating a mess. Temporary disappearance of lanes makes editing complex. Routing ultimately ends up as a lowest common denominator result. The alternative method of representing this same street is as a series of individual lines. But this is equally problematic. In this model, the street loses its coherence as a single entity - humans think of it as a street with multiple uses (walking, cycling, driving, trees). Where people have done this, attributes such as street names need to be kept in sync, and in practice separate pavements often fail to have names attached. Concepts such as the ability to cross from one side of the road to the other (or even switch lanes) are not modelled, with the result that a router may take the user to the end of the street then back down. And cartography ends up showing a series of parallel lines which looks messy and does not match the human perception of a street. The bicycle tagging page on OSM provides a perfect demonstration of the current problem: https://wiki.openstreetmap.org/wiki/Bicycle It shows the complexity of representing many common scenarios, with increasingly incomprehensible tagging combinations. No router implements anything like all of this, and even expert OSM contributors would shy away at bothering to add this data. Cycleways indeed are a good general example of inconsistent tagging. Cycleways separate to a road are sometimes tagged as an attribute of the street and sometimes as a separate geometry. What about a hybrid/stepped cycle lane of the kind seen in Copenhagen - is that a cycle lane or a cycleway? Do lane counts include cycle lanes or not? How is obstructive car parking represented? Is the one-way indication applicable to the cycle lane on the road? And so on. Another example is junctions. Should traffic signals be treated spatially (i.e. represent the location of the traffic heads), or should they be treated linearly so that routing works properly? How should the linear model work accurately when there is only a single geometry for multiple directions? Have a look at the roads around the Arc De Triomphe in Paris - it is completely impossible for a routing engine to work out exactly how many signal delays should actually be attributed based on the presence of the marking of traffic signals in the data: https://www.openstreetmap.org/#map=17/48.87391/2.29536 This talk will discuss these cases, and provide a starting point for discussion on what should be done to improve the situation. As people are ever keener to add more detail to the map, and as more and more mainstream users look to OSM, we have to ask whether the current model is arguably creaking too heavily. Is there a way that we can represent spaces as a set of interconnected flows in some way? The speaker, Martin Lucas-Smith, is one of the developers of CycleStreets, one of the earliest and most established dedicated cycle routing engines. As such, he has spent many years considering the kinds of tradeoffs represented by the current OSM data model. abou

This study adopts a statistical approach based on Exploratory Spatial Data Analysis to identify underlying contribution patterns of OpenStreetMap (OSM). Univariate and multivariate analyses on a number of variables computed from OSM history on a regular hexagonal grid in Milan (Italy) allow to detect a number of both local clusters and local outliers, which shed light on the complexity of OSM temporal evolution driven by active local contributors and communities, data imports and mapping parties. Compared to traditional geospatial data sources, a major advantage of OpenStreetMap (OSM) is the availability of its full history. In literature, OSM history has been exploited for a number of purposes. The most frequent is intrinsic quality assessment, which - in contrast to extrinsic assessment, where OSM quality is evaluated through comparison against a reference dataset - estimates OSM quality by only looking at its temporal evolution. OSM history has been also explored to gain insights into the project's contribution patterns, e.g. history and profiling of contributors; origin, amount, nature and frequency of edits; spatio-temporal evolution of the whole OSM database - or parts thereof, such as road networks and buildings - in specific areas, or after specific events like natural disasters; and spatial analysis of contributor and contribution patterns. This work fits into the context of OSM intrinsic assessment by proposing a statistical approach based on Exploratory Spatial Data Analysis, and in particular spatial association, aimed at uncovering underlying history-based patterns of OSM data. More in detail, spatial association is investigated in both the univariate and multivariate contexts, i.e. in the cases - respectively - when one variable and multiple variables (together) are examined. The univariate analysis is performed using the Local Moran’s I indicator, which provides a robust classification method to detect statistically significant patterns (compared to the hypothesis of randomness) and define the spatial association type at each location in the dataset. The association type reflects the local characteristics of the variable at each location and its surroundings. Hence it allows detecting clusters, i.e. local patterns of similar (either high or low) values, as well as outliers, i.e. local patterns of dissimilar values (either low values surrounded by high values or viceversa). Instead, the multivariate Geary’s c indicator is employed to detect local association patterns resulting from the joint spatial interaction of two or more variables. A multivariate pattern classification comparable to the one of the univariate case is achieved through a novel classification method developed by the authors. This consists of a comparison of local and global centrality measures (means and medians) for the computed distribution of the multivariate Geary’s c, to produce classification maps of clusters and outliers. The analysis is performed on Milan Province (Northern Italy), counting a population of more than 3 million inhabitants on a surface of about 1.500 km². This area is sampled using a regular hexagonal grid with side of the hexagon equal to 1000 m, producing a total of 684 cells. The analysis is focused on the history of OSM nodes only, with the following hypotheses: only nodes with at least one tag are considered; a new version of a node is counted only when there is a change in tags (not in geometry); only the nodes which currently exist in the OSM database are considered. With this in mind, for each grid cell a number of history-based variables are computed: total number of different contributors who have edited OSM nodes; average number of different contributors who have edited each OSM node; average date of creation of the OSM nodes; average date of last edit of the OSM nodes; average number of versions of the OSM nodes; average frequency of update of the OSM nodes. These values are derived from the processing of the OSM Full History Planet file (downloaded in May 2019) and its conversion into a SpatiaLite database after an intersection with the study area, followed by the computation of the variables for each grid cell. The univariate analysis, performed using the QGIS Hotspot Analysis plugin developed by the authors, highlights different spatial associations for the different variables. While some of them (such as total and average number of contributors and average version) clearly show clusters of high values in correspondence of the most urbanized areas and clusters of low values in the non-urban peripheral areas, spatial association patterns are more heterogeneous for other variables such as the average update frequency. Multivariate analyses are then performed to detect the spatial patterns derived from the joint interaction between two and more of the variables considered. Despite each variable has its own spatial pattern when taken alone, their combination (especially when adding more a

Our data model is impractical. You know that. Even OGC Simple Features are better. Changesets and versions promised easier reverting — is it simple yet? We have added a lot of features to API 0.6 over the past ten years, but should we have? Let's see what went wrong and what we can improve. People often come to me saying, changesets with huge bounding boxes are impossible to validate. Come on. You know changesets were not meant to group edits by any criteria. Developers look at the data model and derive user experience from it — and it obviously does not work. Every instance of OSM data needs to be preprocessed, converted, filtered, layered, postprocessed and thrown away. We need to stop looking at OSM as a database and start treating it like a map. In this talk I will highlight what's wrong with the current state of API, including both the actual REST API and the server side. Things like topology, notes, GPX traces and stuff: they were coded when the project was small, but the model starts to show its age — and few people know what to do, besides adding more mappers. How come Overpass API became the better API, and what can we learn from it? Changesets should be abandoned by user-facing tools: let's imagine how the mapping, the validation, the undoing of changes would work if we didn't rely on changesets or actually anything API provides. Can we do something to improve data quality right now? Or can we work towards API 0.7, that would help keep the map not only the most complete, but also the most recent? Let's take a step back and imagine how OpenStreetMap should have been working, to make it more fun to work with, while keeping its versatility and simplicity. I have been involved in a couple API 0.7 discussions, made a few tagging proposals and wrote an editor and a change rollback script. That doesn't make me an expert — there are no experts in OpenStreetMap — but it gave me some ideas on how things could be better. Maybe together we will have a clearer path towards the better OpenStreetMap. about this event: https://pretalx.com/sotm2019/talk/V7NUWP/

An analysis of Notes, based on local experience of managing notes. Over 1 735 319 notes have been added to OSM, currently 416 224 notes are still open. Even looking at a small area such as Edinburgh, the city I live in, we have around 10 new notes added every day. It's interesting to note the motivation of people adding notes, many are added by regular experienced mappers for changes that need to happen in the future, some are added by local businesses or anonymous users altering us to problems on the map and some by non technical users for changes that are required. These note encapsulate a few different categories: Things that can be fixed quickly and the note closed straightaway. We then have short to medium term notes, such as shops closing or road closures that may be for issues for between days and months. Then finally then some of the very long term items, such as the construction of the Forth Crossing, New Hospitals or Housing Estates that may be tracking developments for years. But with so many notes remaining open, issues can very easily be missed. I will briefly review some of the tools available for tracking notes, and talk about how we deal with notes including some of our local tests with using github issues to track some of the longer term issues. Finally as well as hopefully look at some ways of managing notes. Hopefully with some prototypes for ways that notes might be improved either directly on the OSM site or via an external site. about this event: https://pretalx.com/sotm2019/talk/SKVRRL/

OpenStreetMap enables people to use third-party apps that seem to be more suitable for privacy-conscientious users, but are we as users really private when using OSM-based apps? In mobile applications users generally don’t have control over what gets transmitted over the network. This means that people even in the age of the GDPR are not aware what they expose about themselves when using Android or iOS apps. This talks goes through a few popular open and closed source OSM apps and shows what gets transmitted about you and to whom. Additionally, it shows whether removing ads through in-app purchase gives users of those apps more privacy. Furthermore it will be demonstrated which tracking services are most often used and which risks of de-anonymization could arise from this. Also a brief discussion whether and how software developers can make their software more privacy-friendly will take place. Are users aware which data gets sent to third parties and are they consenting? Do they have a choice? And is this tracking generally bad or can it improve user experience in return? Are there apps which are suitable for people who want to stay private? Is it possible to prevent tracking and how? This talk is going to compare several OSM apps in regards to their privacy levels, but also show how closed data, commercial competitors are performing. about this event: https://pretalx.com/sotm2019/talk/7LMH8R/

OpenStreetMap's processes are carefully designed to minimize the privacy footprint of the mappers. Nonetheless, the principle that any edit shall be attributable means that some data is still recorded. An overview is given which data is recorded at all and which of it gets available to whom. OpenStreetMap surveys data about places, not about persons. Thus privacy sensitive data in the geodata is very rare and always unwanted. Likewise, the principle of distributing the data allows data consumers of the geodata to stay as anonymous as they want. Mappers can contribute with pseudonyms, although not completely anonymous. However, for both the social features of OpenStreetMap and the purpose of attribution for the edited data it is necessary to collect some privacy related data. A useful starting point to see your own data footprint is the tool HDYC. All the edits you make are grouped into changesets, and the editing software will urge you to add a comment per changeset. As both the edits and the changesets carry dates it is possible to track your activity times. The nature of some edits may suggest local knowledge thus that you actually have been at the mapped places. The kind of edited objects and the mapping standards can be checked by every other contributor as well. Most often, this is simply a reason to be proud of the achievements, but you should know and check before it might get a matter of concern. Using separated accounts for different mapping tasks is often an appropriate solution and well-accepted in the community. OpenStreetMap offers additional ways to interact: you can leave comments on changesets and notes on the map, you can discuss on mailing lists or the forum, or you can answer questions on help. You can write documentation on the wiki. All of these channels have their own rules with regard to how long the data is stored, how it is searchable, and whether you can hide or delete your contributions. The talk presents the data traces of each channel and discusses strategies to get the desired degree of privacy. about this event: https://pretalx.com/sotm2019/talk/XRL7VK/