Maximizing the reuse of Open Transport Data Pieter Colpaert Ghent University - iMinds/imec 

How far do you live from work? 

km or min? 

Imagine a program calculating distance in minutes What data would you need? 

Transport has become a data sharing problem How can we fix it? 

Sharing data between 2 systems Your system Third party system Agree on a protocol Will determine which questions can be answered in a timely fashion Can ask questions to your system as previously agreed 

Sharing data on the Web Your system ? ? ? ? ? ? Maximizing reuse → need to raise the interoperability 

↓ Querying syntactic semantic technical legal When I have got 2 datasets, how easy is it to use them as if they were 1? 

OpenDefinition.org ↓ Querying syntactic semantic technical legal 

reuse is allowed Documents on the web reuse in a gray zone unauthorised reuse 

A story of raising interoperability ↓ Querying syntactic semantic technical legal When I have 2 datasets, how easy is it to turn them into 1 dataset? → Open Definition & open licenses 

A story of raising interoperability ↓ Querying syntactic semantic technical legal When I have 2 datasets, how easy is it to turn them into 1 dataset? → Open Definition & open licenses → The Internet: exchanging data world-wide 

A story of raising interoperability ↓ Querying syntactic semantic technical legal When I have 2 datasets, how easy is it to turn them into 1 dataset? → Open Definition & open licenses → The Internet: exchanging data world-wide → JSON, XML, CSV, … Open Standards 

name type same as location iMinds company IBBT Gaston Crommenlaan 8 { “iMinds” : { “type” : “company”, “same as” : “IBBT, “location” : “Gaston Crommenlaan 8” } } company IBBT Gaston Crommenlaan 8 Table / CSV / Spreadsheet JSON XML Serialisations 

name type same as location iMinds company IBBT Gaston Crommenlaan 8 . . “Gaston Crommenlaan 8” . Table / CSV / Spreadsheet triples Triple structure { “iMinds” : { “type” : “company”, “same as” : “IBBT, “location” : “Gaston Crommenlaan 8” } } company IBBT Gaston Crommenlaan 8 JSON XML 

World Wide Web iMinds same as IBBT iMinds is a company IBBT located at Gaston Crommenlaan 8 Machine 1 Machine 2 Machine 3 Linked data 

Problem The word company is ambiguous. How can we make sure that machines understand each other? semantic interoperability What about “is a”? and what about “iMinds”? 

Solution iMinds → http://data.kbodata.be/organisation/0866_386_380#id is a → http://www.w3.org/1999/02/22-rdf-syntax-ns#type Company → http://www.w3.org/ns/regorg#RegisteredOrganization Uniform Resource Identifiers (URIs) 

E.g., Linked Datex and Linked GTFS Vocabularies at http://vocab.datex.org/terms http://vocab.gtfs.org/terms E.g., Searching for Parking Facilities with Linked Data thanks to “rich snippets” But is that it? 

A story of raising interoperability ↓ Querying syntactic semantic technical legal When I have 2 datasets, how easy is it to turn them into 1 dataset? → Open Definition & open licenses → The Internet: exchanging data world-wide → JSON, XML, CSV, … Open Standards → using URIs instead of local identifiers 

Where can you get in what amount of time? under specific conditions: taking into account: multimodality, criminality, your subscriptions, what you’re carrying, disabilities, etc 

data dump Route planning algorithms as a service 

A long tail for transport data services ... Hard to guess which kind of queries will be needed 

Can we find a way to publish for example public transport data while minimizing federated reuse cost? 

Data needed for algorithm a connection departureTime + departureStop arrivalTime + arrivalStop another connection departureTime + departureStop arrivalTime + arrivalStop 

time * The Connection Scan Algorithm (CSA) And this is the algorithm* ~ creating a minimum spanning tree through a sorted directed acyclic graph Squares are connections 

Resource X Resource ... Resource 2 Resource 1 time nextPage nextPage When published in pages on the Web, route planning will need X requests instead of 1 

Try it yourself at http://LinkedConnections.org 

Striking the golden mean? Data dumps Smart servers Data publishing (cheap/reliable) Data services (rather expensive/unreliable) Entire query languages over HTTP Dataset split in fragments Smart agents algorithms as a service 

Global interoperability for Route Planners? ↓ Querying syntactic semantic technical legal → Open Definition & open licenses → The Internet: exchanging data world-wide → JSON, XML, CSV, … Open Standards → Work in progress linkedconnections.org → using URIs instead of local identifiers 

Checklist Open (Transport) Data Do you have an open license on your data? Is it shared publicly on the Web in an open format (html/css/xml/json…)? Do you identify things in a globally interoperable way? How easy is it to include your dataset in a federated query? Are you exposing basic reusable building blocks for your dataset? 

A world where knowledge creates power for the many, not the few Questions? @pietercolpaert http://pieter.pm