This document evaluates the quality of OpenStreetMap (OSM) data compared to Ordnance Survey data. It finds that for major roads, 80% of OSM data falls within a 20m buffer of Ordnance Survey data. For smaller roads, completeness increases with more users per area, but positional accuracy does not clearly increase above 5 users per area. While OSM data quality is high in areas with aerial imagery, Linus' Law about quality increasing with more users does not seem to directly apply to OSM. More research is needed on quality with fewer users and without aerial imagery.
Beyond good enough? Spatial Data Quality and OpenStreetMap dataMuki Haklay
State of the Map '09 presentation. Covering spatial data quality and comparison of Ordnance Survey data (Meridian 2, 10K Raster, MasterMap ITN) to OSM for England.
Some material appeared in previous presentation.
Accessibility Analysis and Modeling in Public Transport Networks - A Raster b...Beniamino Murgante
Accessibility Analysis and Modeling in Public Transport Networks - A
Raster based Approach
Morten Fuglsang, - National Environmental Research Institute, Aarhus
University and Aalborg University Copenhagen
Henning Sten Hansen - Aalborg University Copenhagen
Bernd Münier - National Environmental Research Institute, Aarhus University
Beyond good enough? Spatial Data Quality and OpenStreetMap dataMuki Haklay
State of the Map '09 presentation. Covering spatial data quality and comparison of Ordnance Survey data (Meridian 2, 10K Raster, MasterMap ITN) to OSM for England.
Some material appeared in previous presentation.
Accessibility Analysis and Modeling in Public Transport Networks - A Raster b...Beniamino Murgante
Accessibility Analysis and Modeling in Public Transport Networks - A
Raster based Approach
Morten Fuglsang, - National Environmental Research Institute, Aarhus
University and Aalborg University Copenhagen
Henning Sten Hansen - Aalborg University Copenhagen
Bernd Münier - National Environmental Research Institute, Aarhus University
Public Transport Accessibility Index for Thiruvananthapuram Urban AreaIOSR Journals
Transportation planning is an important part in the development of a region. An effective transport
system and associated urban forms will improve the economic and social opportunities. Accessibility and
mobility are the two main parameters which contribute to the effective transportation system. In this paper, the
accessibility to the public transportation system is identified for the selected study area with the help of an
indexing system. The sub-area in the region was thus graded based on their accessibility and the obtained
values are found to resemble the real world.
Accessibility, indexing system, public transport system, transport planning
Road2Vec: Measuring Traffic Interactions in Urban Road System from Massive Tr...Song Gao
Good characterization of traffic interactions among urban roads can facilitate traffic-related applications, such as traffic control and short-term forecasting. Most studies measure the traffic interaction between two roads by their topological distance or the correlation between their traffic variables. However, the distance-based methods neglect the spatial heterogeneity of roads’ traffic interactions, while the correlation-based methods cannot capture the non-linear dependency between two roads’ traffic variables. In this work, we propose a novel approach called Road2Vec to quantify the implicit traffic interactions among roads based on large-scale taxi operating route data using a Word2Vec model from the natural language processing (NLP) field. A case study on short-term traffic forecasting is conducted with artificial neural network (ANN) and support vector machine (SVM) algorithms to validate the advantages of the presented method. The results show that the forecasting achieves a higher accuracy with the support of the Road2Vec method than with the topological distance and traffic correlation based methods.
A macroscopic traffic model based on the Markov chain process is developed for urban traffic networks. The method utilizes existing census data rather than measurements of traffic to create parameters for the model. Four versions of the model are applied to the Philadelphia regional highway network and evaluated based on their ability to predict segments of highway that possess heavy traffic.
Application of a Markov chain traffic model to the Greater Philadelphia RegionJoseph Reiter
A macroscopic traffic model based on the Markov chain process is developed for urban traffic networks. The method utilizes existing census data rather than measurements of traffic to create parameters for the model. Four versions of the model are applied to the Philadelphia regional highway network and evaluated based on their ability to predict segments of highway that possess heavy traffic.
This webinar will walk you through several resources from Microsoft that will help you, your staff, or your constituents get the training they need to use Microsoft software more confidently. We’ll look at resources that address a variety of training scenarios, skill levels and products. We will cover:
Public Transport Accessibility Index for Thiruvananthapuram Urban AreaIOSR Journals
Transportation planning is an important part in the development of a region. An effective transport
system and associated urban forms will improve the economic and social opportunities. Accessibility and
mobility are the two main parameters which contribute to the effective transportation system. In this paper, the
accessibility to the public transportation system is identified for the selected study area with the help of an
indexing system. The sub-area in the region was thus graded based on their accessibility and the obtained
values are found to resemble the real world.
Accessibility, indexing system, public transport system, transport planning
Road2Vec: Measuring Traffic Interactions in Urban Road System from Massive Tr...Song Gao
Good characterization of traffic interactions among urban roads can facilitate traffic-related applications, such as traffic control and short-term forecasting. Most studies measure the traffic interaction between two roads by their topological distance or the correlation between their traffic variables. However, the distance-based methods neglect the spatial heterogeneity of roads’ traffic interactions, while the correlation-based methods cannot capture the non-linear dependency between two roads’ traffic variables. In this work, we propose a novel approach called Road2Vec to quantify the implicit traffic interactions among roads based on large-scale taxi operating route data using a Word2Vec model from the natural language processing (NLP) field. A case study on short-term traffic forecasting is conducted with artificial neural network (ANN) and support vector machine (SVM) algorithms to validate the advantages of the presented method. The results show that the forecasting achieves a higher accuracy with the support of the Road2Vec method than with the topological distance and traffic correlation based methods.
A macroscopic traffic model based on the Markov chain process is developed for urban traffic networks. The method utilizes existing census data rather than measurements of traffic to create parameters for the model. Four versions of the model are applied to the Philadelphia regional highway network and evaluated based on their ability to predict segments of highway that possess heavy traffic.
Application of a Markov chain traffic model to the Greater Philadelphia RegionJoseph Reiter
A macroscopic traffic model based on the Markov chain process is developed for urban traffic networks. The method utilizes existing census data rather than measurements of traffic to create parameters for the model. Four versions of the model are applied to the Philadelphia regional highway network and evaluated based on their ability to predict segments of highway that possess heavy traffic.
This webinar will walk you through several resources from Microsoft that will help you, your staff, or your constituents get the training they need to use Microsoft software more confidently. We’ll look at resources that address a variety of training scenarios, skill levels and products. We will cover:
Presented at the 46th Society of Cartographers Summer School in Manchester on September 10 2010. The abstract for the talk was as follows: "OpenStreetMap is coming of age, but as it starts to be used more in the mainstream, the age-old questions of quality and completeness are coming to the fore. A range of data sources have been used to build up the map in the UK, from GPS traces to aerial imagery, historic mapping, NaPTAN and the OS Open Data release, each with their own benefits and limitations. This talk looks at a number of studies and tools developed to quantify, compare and address accuracy and coverage of the project in the UK, in an attempt to answer the key questions - is it complete yet and just how good is it?"
Improving transport in Malta using GIS and LBSMatthew Pulis
A presentation prepared to the University of Malta as part of my MSc. Informatics. This seminar discusses ways and improvements how can a GIS driven system help and improve the current situation in Malta. This presentation also provides a survey discussing how the Maltese view the public transport and gives out interesting conclusions as to where the GIS needs to tackle. The study focuses mainly on ways as to where and how to improve the routes, promoting cultural places, buses ETA and taxi fleet handling amongst others.
Qualità dei dati OpenStreetMap: sperimentazioni sulla città di Milano e risul...Marco Minghini
These slides were presented during the Italian OpenStreetMap conference - OSMit 2016 (http://conf.openstreetmap.it), held in Milan (Italy) on May 20-21, 2016. They include a description of some ongoing research works on OpenStreetMap which are under development at the GEOlab (http://geolab.como.polimi.it) of Politecnico di Milano.
Graph Centric Analysis of Road Network Patterns for CBD’s of Metropolitan Cit...Punit Sharnagat
OSMnx is a Python package to retrieve, model, analyze, and visualize street networks from OpenStreetMap.
OpenStreetMap (OSM) is a collaborative mapping project that provides a free and publicly editable map of the world.
OpenStreetMap provides a valuable crowd-sourced database of raw geospatial data for constructing models of urban street networks for scientific analysis
What is European Location Framework and what is needed to make geospatial reference data to work in Europe based on INSPIRE. Presentation at the INSPIRE conference 2011.
Integrating spatial and thematic data: the CRISOLA case for Malta and the Eur...Beniamino Murgante
Integrating spatial and thematic data: the CRISOLA case for Malta and the European project Plan4all
Saviour Formosa - Institute of Criminology, University of Malta
Vincent Magri - Fondazzjoni Temi Zammit, University of Malta
Julia Neuschmid, Manfred Schrenk - Department for Urbanism, Transport, Environment and Information Society, Central European Institute of Technology, Austria
The Distributional Impacts of Transportation Networks in Chinamalin84
The presentation slides of "The Distributional Impacts of Transportation Networks in China", published in the Journal of International Economics in 2024
National Highway Alignment from Namakkal to Erode Using GISIJERA Editor
The vision of the Highway Alignment is to increase the capacity, connectivity, efficiency and safety of the Highways System so as to enable balanced socioeconomic development of all sections of the people and all regions from NAMAKKAL to ERODE via and to reduce the traffic and travelling of the state. It is to establish shortest path for road network time in the roads which provide a better and comfortable base for updating the traffic and other related information in road administration. It is to identify the short route for the vehicles traveling from NAMAKKAL to ERODE and to reduce the time travel for the vehicles with possible paths or routes or places for laying eco-friendly highway. To optimize the route for the vehicles traveling from NAMAKKAL to ERODE using GIS with Network analysis tools. From this we can find the suitable route for peoples to carry out without any traffic disturbances and protecting the environment. It also took advantages of GIS capabilities that offer the ability to overlay maps, merge them, and perform spatial analysis on various layers of information in either two or three dimensions
APPLICABILITY OF CROWD SOURCING TO DETERMINE THE BEST TRANSPORTATION METHOD B...IJDKP
Traffic is one of the most significant problem in Sri Lanka. Valuable time can be saved if there is a proper way to predict the traffic and recommend the best route considering the time factor and the people’s satisfaction on various transportation methods. Therefore, in this research using location awareness applications installed in mobile devices, data related to user mobility were collected by using crowdsourcing techniques and studied. Based on these observations an algorithm has been developed to overcome the problem. By using this, the best transportation method can be predicted as the results of the research. Therefore, people can choose what will be the best time slots & transportation methods when planning journeys. Throughout this research it has been proven that for the Sri Lankan context, the data mining concepts together with crowdsourcing can be applied to determine the best transportation method.
Similar to 4B_1_How many volunteers does it take to map an area well (20)
8A_2_A containment-first search algorithm for higher-order analysis of urban ...
4B_1_How many volunteers does it take to map an area well
1. How Many Volunteers Does It Take To Map An Area Well? Dr Muki Haklay Department of Civil, Environmental and Geomatic Engineering, UCL m.haklay@ucl.ac.uk AamerAther (M.Eng 2009), Sofia Basiouka (MSc GIS 2009) and NaureenZulfiqar (M.Eng 2008) Ordnance Survey data was kindly provided by the Ordnance Survey research unit. OSM data was provided by GeoFabrik & CloudMade
2. Outline A bit about quality of geographical information Evaluation of OSM with Meridian data set Evaluation of OSM with MasterMap Linus’ low –more users: higher quality?
3. The quality issue How good it the data? First question: good for what? Subjective quality – fitness for purpose/use Second question: how to measure? Objective quality – but need to evaluate it in light of the first question
4. The quality issue How good it the data? Positional accuracy – the position of features or geographic objects in either two or three dimensions Temporal accuracy – how up to date is the data? Does it presents the existing situation and when will it be updated? Thematic/attribute accuracy – for quantitative attributes (width) and qualitative attributes (geographic names) Completeness – The presence and absence of objects in a dataset at a particular point in time Logical consistency –adherence to the logical rules of the data structure, attribution and relationships
5. The ‘problem’ “We know little about the people that collect it, their skills, knowledge or patterns of data collection” “Loose coordination and no top-down quality assurance processes – can’t produce good data” “It is not complete and comprehensive – there are white areas”
11. Users Limited ‘on the ground’ collaboration. Important as this can be the main source of quality assurance - ‘Given enough eyeballs, all bugs are shallow’ (Raymond, 2001) Translate to VGI it might mean:“The more users there are per area, the better is the positional and attribute quality” But does Linus’ law apply to OSM (and to VGI)?!?
12. Accuracy and Completeness- Study I Comparing OSM to OS Meridian 2 roads layer Maridian 2 -Motorways, major and minor roads are... Complex junctions are collapsed to single nodes and multi-carriageways to single links... some minor roads and cul-de-sacs less than 200m are not represented... Private roads and tracks are not included... Nodes are derived from 1:1,250-1:2,500 mapping, with 20m filter around centre line generalisation
14. Goodchild and Hunter (1997), Hunter (1999) method Assuming that one dataset is of higher quality Create buffer around the dataset with known width Calculate the percentage of the evaluated dataset that falls within the buffer
16. Comparison II – Ordnance Survey Master Map Data used for comparison: OS MasterMap Integrated Transport Network (ITN) layer ITN consists of road network information The most accurate and up-to-date geographic reference for Great Britain’s road structure Any major real world changes are updated within 6 months Used for numerous applications e.g. Transport management systems, road routing, emergency planning...
24. Completeness – bulk method Assumption: as Meridian 2 is generalised, so for each sq km: If Total length(OSM roads)>Total length(Meridian 2 roads) Than OSM is more complete than Meridian 2 The comparison can also includes attributes, by testing for the number of objects with complete set of values
31. Completeness with attributes The test for completeness with attributes checks that roads and streets names have been completed Until the release of Ordnance Survey data in 1st April 2010, this was a good indication for ground survey of an area
38. Conclusions OSM quality is high – and it is assumed that the quality is coming from aerial imagery Linus’ Law does not seem to apply in a straight forward manner – at least not from 5 and above More research is required for lower numbers or participants and different quality of imagery
39. Further reading Haklay, M., 2008, How good is OpenStreetMap information? A comparative study of OpenStreetMap and Ordnance Survey datasets for London and the rest of England, submitted to Environment and Planning B. Haklay, M. And Weber, P., 2008, OpenStreetMap – User Generated Street Map, IEEE Pervasive Computing. Haklay, M., Singleton, A., and Parker, C., 2008, Web mapping 2.0: the Neogeography of the Geoweb, Geography Compass Haklay, M., 2008, Open Knowledge – learning from environmental information, presented at the Open Knowledge Conference (OKCon) 2008, London, 15 March. Haklay, M., 2007, OSM and the public - what barriers need to be crossed?presented at State of the Map conference, Manchester, UK, 14-15 July. To get a copy, write to m.haklay@ucl.ac.uk , or get them on povesham.wordpress.com
Editor's Notes
The higher level dataset to be used was OS MasterMap. The Ordnance Survey’s MasterMap is a database that records every fixed feature of Great Britain larger than a few metres in one continuous digital map – It is a framework on which future OS products will be based The ITN layer is one of four layers, and the layer used for this project. ITN obtained from Edina, OSM for CloudeMadeITN data obtained in GML format, which was then converted to shp file format, and the required OSM downloaded as shp file.
- 25km square grid , based on OS 1:10000 grid tilesThe tiles were chosen to cover a range of London, North, South, East & West, two close and two further out from the centre, so that a good sample was chosen
Requires the use of a reference source (ITN) and a test source (OSM)Here we have an example of an ITN and corresponding OSM road feature.ITN is the higher level dataset, and therefore the ITN road feature is considered to be the actual centreline of the road. A buffer of width x is created around the ITN featureThe proportion of the OSM road that lies that lies within the buffer is then calculatedThis analysis carried out for every A-road, B-road and motorway feature in the datasets
The results are very high, indicating that the positional accuracy of OSM is very good.In particular, the South London tile had an average of 92.62% overlap for A-roads, and North/Central London tile had 81.46% overlap for B-roads.Only one motorway segment (very high)
- Results maps for each of the four test regions- The distribution of results in the histogram is clearly illustrated by the results maps. Anything above 90% overlap in red, between 80-90% in orange, and between 70-80% in yellow.