This repository demonstrates / documents how Helsinki Region Travel Time Matrix 2015 is calculated. Dataset was produced by Accessibility Research Group, University of Helsinki.
Contents:
- What is Helsinki Region Travel Time Matrix 2015?
- Attributes of Helsinki Region Travel Time Matrix 2015
- How calculations were done?
- Licence
- How to cite this work?
- Codes
- Contribution / Contact
Helsinki Region Travel Time Matrix 2015 is a dataset that contains travel time and distance information of the routes that have been calculated from all 250 m x 250 m grid cell centroids (n = 13231) in the Capital Region of Helsinki (see this map) by walking, public transportation (PT) and private car. Calculations were done separately for two different time of the day using rush hour (08:00-09:00) and midday (12:00-13:00) schedules/traffic conditions. The grid cells are compatible with the statistical grid cells in the YKR (yhdyskuntarakenteen seurantajärjestelmä) data set produced by the Finnish Environment Institute (SYKE).
Dataset is openly available for everyone for free and it can be downloaded from the Accessibility Research Group website (under a Creative Commons 4.0 Licence, see licence text).
Helsinki Region Travel Time Matrix 2015 is closely related to Helsinki Region Travel CO2 Matrix 2015 that is also produced by Accessibility Research Group. More information on how the Helsinki Region Travel CO2 Matrix 2015 was calculated can be found from here.
Scientific examples of the approach used here can be read from the following articles:
- Laatikainen, T., H. Tenkanen, M. Kyttä & T. Toivonen (2015). Comparing conventional and PPGIS approaches in measuring equality of access to urban aquatic environments. Landscape and Urban Planning 144, 22–33.
- Toivonen, T., M. Salonen, H. Tenkanen, P. Saarsalmi, T. Jaakkola & J. Järvi (2014). Joukkoliikenteellä, autolla ja kävellen: Avoin saavutettavuusaineisto pääkaupunkiseudulla. Terra 126: 3, 127-136.
- Salonen, M. & Toivonen, T. (2013). Modelling travel time in urban networks: comparable measures for private car and public transport. Journal of Transport Geography 31, 143–153.
- Jaakkola, T. (2013). Paikkatietopohjainen menetelmä autoilun ajoaikojen ja kokonaismatka-aikojen mallintamiseen – esimerkkinä pääkaupunkiseutu. Pro gradu -tutkielma. Helsingin yliopisto. Geotieteiden ja maantieteen laitos.
- Lahtinen, J., Salonen, M. & Toivonen, T. (2013). Facility allocation strategies and the sustainability of service delivery: Modelling library patronage patterns and their related CO2-emissions. Applied Geography 44, 43-52.
- Jäppinen, S., Toivonen, T. & Salonen, M. (2013). Modelling the potential effect of shared bicycles on public transport travel times in Greater Helsinki: An open data approach. Applied Geography 43, 13-24.
- Salonen, M., Toivonen, T. & Vaattovaara, M. (2012). Arkiliikkumisen vaihtoehdoista monikeskuksistuvassa metropolissa: Kaksi näkökulmaa palvelujen saavutettavuuteen pääkaupunkiseudulla. Yhdyskuntasuunnittelu 3/2012
| Attribute | Definition |
|---|---|
| from_id | ID number of the origin grid cell |
| to_id | ID number of the destination grid cell |
| walk_t | Travel time from origin to destination by walking |
| walk_d | Distance (meters) of the walking route |
| pt_r_tt | Travel time from origin to destination by public transportation in rush hour traffic; whole travel chain has been taken into acount including the waiting time at home |
| pt_r_t | Travel time from origin to destination by public transportation in rush hour traffic; whole travel chain has been taken into account excluding the waiting time at home |
| pt_r_d | Distance (meters) of the public transportation route in rush hour traffic |
| pt_m_tt | Travel time from origin to destination by public transportation in midday traffic; whole travel chain has been taken into acount including the waiting time at home |
| pt_m_t | Travel time from origin to destination by public transportation in midday traffic; whole travel chain has been taken into account excluding the waiting time at home |
| pt_m_d | Distance (meters) of the public transportation route in midday traffic |
| car_r_t | Travel time from origin to destination by private car in rush hour traffic; the whole travel chain has been taken into account |
| car_r_d | Distance (meters) of the private car route in rush hour traffic |
| car_m_t | Travel time from origin to destination by private car in midday traffic; the whole travel chain has been taken into account |
| car_m_d | Distance (meters) of the private car route in midday traffic |
The routes by public transportation have been calculated by using the MetropAccess-Reititin tool which also takes into account the whole travel chains from the origin to the destination:
- possible waiting at home before leaving
- walking from home to the transit stop
- waiting at the transit stop
- travel time to next transit stop
- transport mode change
- travel time to next transit stop
- walking to the destination
Travel times by public transportation have been optimized using 10 different departure times within the calculation hour using so called Golomb ruler. The fastest route from these calculations are selected for the final travel time matrix.
Calculations of 2015 MetropAccess-Travel Time Matrix are based on schedules of Monday 28.09.2015:
- Midday (optimized between 12:00-13:00 ) --> Comparable with 1st version of Helsinki Region Travel Time Matrix (2013)
- Rush hour (optimized between 08:00-09:00) --> New for 2015 version of TTM!
The routes by walking were also calculated using the MetropAccess-Reititin by disabling all motorized transport modes in the calculation. Thus, all routes are based on the Open Street Map geometry. The walking speed has been adjusted to 70 meters per minute, which is the default speed in the HRT Journey Planner (also in the calculations by public transportation).
The routes by car have been calculated in ArcGIS 10.2 software by using MetropAccess-Digiroad tool. MetropAccess-Digiroad dataset (modified from the original Digiroad data provided by Finnish Transport Agency) has been used as Network Dataset in which the travel times of the road segments are made more realistic by adding crossroad impedances for different road classes.
The calculations have been repeated for two times of the day using:
- the "midday impedance" (i.e. travel times outside rush hour)
- the "rush hour impendance" as impedance in the calculations.
The whole travel chain ( "door-to-door approach" ) is taken into account in the calculations:
- walking time from the real origin to the nearest network location (based on Euclidean distance)
- average walking time from the origin to the parking lot
- travel time from parking lot to destination
- average time for searching a parking lot
- walking time from parking lot to nearest network location of the destination
- walking time from network location to the real destination (based on Euclidean distance)
All calculations were done using the computing resources of CSC-IT Center for Science (https://www.csc.fi/home).
Helsinki Region Travel Time Matrix 2015 by Accessibility Research Group / MetropAccess-project (University of Helsinki) is licensed under a Creative Commons Attribution 4.0 International License. More information about license: http://creativecommons.org/licenses/by/4.0/
If the datasets are being used extensively in scientific research, we welcome the opportunity for co-authorship of papers. Please contact project leader to discuss about the matter.
If you use Helsinki Region Travel Time Matrix 2015 dataset or related tools in your work, we encourage you to cite properly to our work.
You can cite to our work as follows:
Data/Tools description:
- Toivonen, T., M. Salonen, H. Tenkanen, P. Saarsalmi, T. Jaakkola & J. Järvi (2014). Joukkoliikenteellä, autolla ja kävellen: Avoin saavutettavuusaineisto pääkaupunkiseudulla. Terra 126: 3, 127-136.
DOI name for the dataset:
- Toivonen, T., H. Tenkanen, V. Heikinheimo, T. Jaakkola, J. Järvi & M. Salonen (2016). Helsinki Region Travel Time Matrix 2015. DOI: 10.13140/RG.2.1.1901.3201
All the codes and analysis steps that have been used to produce the Helsinki Region Travel Time Matrix 2015 are documented separately in here.
Helsinki Region Travel Time Matrix 2015 was created by the Accessibility Research Group at the Department of Geosciences and Geography, University of Helsinki, Finland.
Following people have contributed / are responsible for creating this dataset:
- Henrikki Tenkanen (PhD candidate, project manager, participation in all steps)
- Vuokko Heikinheimo (PhD candidate, dataset production, documentation)
- Tuuli Toivonen (PI, leader of the research group)
- Maria Salonen (project manager, participation in all steps)
- Juha Järvi (BusFaster Ltd, programming and design of the MetropAccess-Reitin)
- Timo Jaakkola (development of the travel time model for private cars)
In addition, we thank CSC - IT Center for Science for computational resources and help. CSC Taito and cPouta computing clusters were used as our workhorses to calculate the travel times/distances (approx. 1 billion routes were calculated) using MetropAccess-Digiroad- and MetropAccess-Reititin Tools.