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Consortium: DEMIS ISIS ITC KIT MKMetric NEA ( Coord ) NESTEAR NTU NTUA OBET STRATA STRATEC TETRAPLAN TIS TML TNO TRT UNIZA. ETISplus Final Workshop Validation. Brussels 5-11-2012 Daniela Carvalho (TIS). Validation in ETIS plus. Concept and reasoning.
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Consortium: DEMIS ISIS ITC KIT MKMetric NEA (Coord) NESTEAR NTU NTUA OBET STRATA STRATEC TETRAPLAN TIS TML TNO TRT UNIZA ETISplus Final WorkshopValidation Brussels 5-11-2012 Daniela Carvalho (TIS)
Concept and reasoning Transport modeling is essential to policy assessment and development: requirement for good quality input data to support models, evaluation methodologies and indicator frameworks Information integration and consistent data source minimise the risks and problems of data interpretation arising from the heterogeneous methodologies associated with the available data sources ETISplus, by targeting the data needs of the European Commission’ s reference transport models aims to create a central resource of policy oriented datasets which will be of immediate use to policy analysts The data gathered in this project, as well as the data to be gathered in later updates of the ETIS database, need to be checked for quality and consistency, in a structured manner WP10 fully dedicated to validation
Validation dimensions Validation Corrections to implement Internal External Freight Passenger EU Models (WS March 2012) Supporting data Nat Experts (Survey) Suggestions were reverted in databases • Validation in ETISplus had a twofold objective: • to assure that the data fulfils the needs for the transport models in use to support transport policy related measures and actions (external perspective) • to present consistent data, free from obvious mistakes or gaps, in order to turn the database reliable and ready to be used (internal perspective)
ASTRA Trans-Tools V3 Trans-Tools V3 TREMOVE Compilation and documentation of the conclusions and recommendations = inputs for database developers = ASTRA LOGIS POLES CGEurope SASI NEAC RHOMOLO VIA VACLAV • Focus of External Validation with EU Transport Models: • How does ETIS+ fulfils the current needs for on-going models and policy monitoring • Ascertain whether the content of ETIS+ is suitable to the data needs from major European modelers and policy makers • Identify possible gaps or missing indicators
General data • 1) GDP per Capita 2005 • 2) GDP per Capita 2010 • 3) Motorization Rate Freight 2005 • 4) Motorization Rate Freight 2010 • 5) Motorization Rate Passenger 2005 • 6) Motorization Rate Passenger 2010 • 7) Freight Performances in Ton-Km car and rail • 8) Passenger-kilometers car and rail • Airport data • 9) Air passenger accessibility 2010 • 10) Air freight accessibility 2010 • 11) Airport freight 2005 • 12) Airport freight 2010 • 13) Airport passenger 2005 • 14) Airport passenger 2010 • Rail data • 15)Rail freight assignment 2005 • 16) Rail Freight Net Max. Speed 2005 • 17) Rail Passenger Net Max. Speed 2005 • 18) Passenger trips by rail • Road data • 19) Road freight assignment 2005 • 20) Passenger trips by car • Waterborne data • 21) Sea Port Freight 2005 • 22) Sea Port Passenger 2005 • 23) Inland ports 2010 • 24) IWW assignment 2005 • Focus of External Validation with National Experts: • Evaluation of outputs generated focusing in particular in own country data: accuracy /plausibility / coherence /comprehensiveness • Mostly through graphical visualization (ETIS-VIEW tool)
Internal Validation Exercise • Data Screening => structural checks implemented throughout the development of the database software platform: • Input data errors, • Measurement errors, • Sampling errors & Transfer errors, • Specification errors, • Aggregation errors
Internal Validation Exercise Supporting Data • Socio-economic • Networks (road, rail, air, inland, maritime) • Level of Service • Transport External Impacts Freight-Logistics • International Freight Flows • National Freight Flows • Logistic Data: transport logistics and distribution / inventory, containers Aggregated checks, Reasonableness Checks (NTUA, NESTEAR, TRT) Passengers Demand • Road, rail, air transport • Public Transport • Coach transport • Short distance Transport • Data Evaluation • 3 main issues: consistency of data, consistency over time, and data continuity check (checking of graphic attributes) • Continuous interaction between “validators” and “developers”
Socioeconomic datasets: Techniques used Missing value Missing value analysis between EU27 and other countries. Total sum of all subsets The sum of all subsets should reasonably be equal to the total population of the set. E.g. the sum of males and females in a region should be equal to the total population of the region. The sum of sub classes (e.g. population by gender and age group) should reasonably be equal to the total number of population. + = • Identification of extreme values • Certain parameter values have been statistically analyzed using descriptive statistics • in order to identify extreme (erroneous or suspicious) values in the associated datasets • Min, 5% Percentile, Average, 95% Percentile, Max values • number of cases in the range of [0-2%), • number of cases exceeding the 2% threshold, etc.) Comparison with alternative sources In this test parameter values are compared with associated values of alternative sources.
Socioeconomic dataset: Parameters and tests performed Excel files: One for each parameter containing detailed analysis and results (all erroneous and suspicious values) Corrections incorporated by developers
Networks: Techniques used Test #1: Check for not connected links of the network Logical Rule: Identification of network links that are not connected. Technique: Topology rule of ArcGIS “do not have dangles” Test #2: Network end points inside the sea Logical Rule: Identification of the terminal points of the network that are outside the land region and indicates if in the Bing Maps these points are actually on land or in the sea. Technique: Topology rule of ArcGIS “must be properly inside”
Networks: Techniques used Testing road network in terms of path selection and travel time duration Greece-Germany (interviews with truck drivers)
Networks: Techniques used Test for network continuity: minimum road paths crossing border points & sea connections through ports
Impedances: Techniques used Air Impedances Test: Calculation of access and flight speed Techniques: a) Check if “Access Time + Flight Time = Total Time, b) Frequency distribution for Access and Flight Speed Road Impedances Test: Calculation of distances between regions (centroids) 1. Calculation of the difference between distances traveling from region A to B minus distances from B to A. 2. Identification of short distances between centroids Regions with road distances less than 20 Km Rail Impedances Test: Calculation of distances between regions (centroids) 1. (as Road Impedances) 2. Identification of regions that have no rail impedances but rail network exists Regions with missing rail freight impedances, while rail network seem to exist
Validation exercise • Validation by comparing ETISplus tables themselves checking logical consistency : • i.e. ∑ loaded goods of all regions =∑ unloaded goods of all regions • tables “Air Freight by OD”, “International Road Freight”, “International Rail Freight”, “IWW Freight”, “International Pipeline Freight” were compared with table “EU Detailed Trade (Comext Transport)” at national level, differentiated by mode of transport • Validation by comparing ETISplus tables with other data source and comparing indicator calculated from ETISplus tables with other data source (reference) • UNECE Transport Statistics, • Sitram • TRM statistics* • CAFT • Port Authority: statistics of “throughput annual” • WTO statistics TRM * The statistics come from the French part of the European survey on road freight transport. In France, it concerns the transport carried out by trucks over 3.5 tons GVW registered in France, and used for hire or reward or on own account
Validation exercise • Checks on trips distribution by distance and by purpose • Correlation with socio economic data e.g. • Correlation between total generated trips and population • Correlation between inter/intra-zonal trips and population • Correlation between attracted BUSINESS trips and WORKING PLACES and GDP • Correlation between attracted COMMUTING trips and WORKING PLACES • Correlation between attracted PRIVATE trips and POPULATION • Correlation between attracted VACATION trips and BED PLACES • Comparison with ETIF statistics in terms of PKM
Learning’s and Recommen-dations • Importance of dedicated validation processes performed by “independent” reviewers in addition to regular validation by developers • Relevance of both internal and external views • External (EU) »» 3 workshops per mode (road, rail, maritime), 1 workshop with Eurostat, 1 workshop with EU models • importance of observed data (vs estimated data), relevance of detailed metadata concerning source and quality of the data collected is stated as a relevant factor • Importance of including additional information, especially concerning prices, taxes and tariffs »» database was shaped in line with expectations, • Provision of reference indicators that could be used for validation purposes • External (MS) »» allowing country experts to visualise its own results • Identification of “new” gaps and uncertainties but particularly provision of new data • Inputs being updated in ETIS+
Learning’s and Recommen-dations • Different validation processes and consistency checks undertaken will be reported in ETIS plus report to be used as guide for future exercises • Highlight the importance of applying different layers of validation processes: • Internal routines by database developers • Internal checks performed by “independent” validators • External validation by users of datasets • External validation by users (policy) • ETIS+ dedicated large efforts towards the requirement for good quality input data to support models • Internal »» strong interaction process between validators and developers • inconsistencies verified (data entry mistakes / wrong data) and corrected • findings of validation included in metadata
Thank you for your attention Consortium: DEMIS ISIS ITC KIT MKMetric NEA (Coord) NESTEAR NTU NTUA OBET STRATA STRATEC TETRAPLAN TIS TML TNO TRT UNIZA Daniela Carvalho daniela.carvalho@tis.pt