D5 Annex report WP 7: ETISDatabase methodology ... - ETIS plus
D5 Annex report WP 7: ETISDatabase methodology ... - ETIS plus
D5 Annex report WP 7: ETISDatabase methodology ... - ETIS plus
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<strong>D5</strong> <strong>Annex</strong> <strong>WP</strong> 7: <strong>ETIS</strong> DATABASE METHODOLOGY AND DATABASE USER<br />
MANUAL – PASSENGER TRANSPORT SUPPLY<br />
As an answer – and this is contrary to earthbound modes – we suggest averaging travel<br />
impedances for the possible routings for an ODpair, based on the probability a customers uses<br />
each of the possible routings.<br />
In a first step, with travel impedances for rail and road between regions (time, costs, frequency)<br />
a mode choice model calculates average impedances for access/ egress of airports. In parallel<br />
connections between airports are calculated within a connectionbuilder (external model or<br />
commercial software available), based on a flight schedule. The costs applying for each<br />
connection are based both on carrier specific tariffs from a data base of a ticket consolidator and<br />
on other variables, like travel distance, carriers used within a specific connection. The latter part<br />
is calculated by a price model for air transport.<br />
The aggregated trip purpose specific travel impedances (time, costs) of connections using the<br />
same sequence of region – airport(s) – region form average travel impedances for each routing.<br />
These routings enter a route choice model calculating the trip purpose specific probability to be<br />
used by the consumer. Adding the route specific travel times weighted by these probabilities<br />
results in trip purpose specific average travel impedances by air as main mode for a travel<br />
between two regions. As a last step one has to add these travel impedances for the specific trip<br />
purposes weighted by the share each trip purpose has on the total air transport demand for the<br />
specific O/D pair.<br />
As the mode air transport does not have a fixed network like e. g. road, impedances mainly<br />
depend on the air services connecting the airports. Hence the base for calculating travel times<br />
for air has to be the schedule of the flights available within a particular period.<br />
As an example concerning the travel times air we show the results of computation for the ODpair<br />
the NUTSregions DE122 (Karlsruhe) and UK A15 (Dundee). The values were calculated<br />
on an existing data base which will be enriched by the data of the sources to be bought within<br />
the <strong>ETIS</strong> project like OAG (air transport), Hafas (for travel impedances by rail between regions<br />
and airports).<br />
40<br />
R20040089.doc<br />
27 May 2004
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