D5 Annex report WP 3: ETIS Database methodology ... - ETIS plus

D5 Annex WP 3: DATABASE METHODOLOGY AND DATABASE USER
MANUAL – FREIGHT TRANSPORT DEMAND
IRL ­4,199 5,960 7,544 1,406 ­24,808 0 2,198 9,567 2,334
DK ­1,847 ­3,821 ­15,360 1,995 1,792 3,403 0 11,875 1,962
EL 942 ­4,224 122 ­1,566 2,281 934 795 0 716
PT 2,109 3,451 ­27,833 3,286 6,498 2,736 1,984 7,769 0
The total error is lower using this method, and although the correlation with distance is still
present, it is also lower.
The conclusion is therefore that a combination of these techniques should be used. The data
should be disaggregated by commodity, and by region where possible. The amoeba algorithm
should be used to establish parameters for the gravity model, using known flows. These
parameters should then be used to seed the region to region matrices, and the Furness algorithm
to build up the O/D matrices.
Method 4: Inclusion of domestic transport to the matrix
In the fourth method domestic transport is included in the O/D matrix. Data about domestic
transport flows is collected from national statistical offices and Eurostat. For a number of
countries region­to­region by commodity type by transport mode information is available. For
other countries only more aggregate data is available. In the latter case, data sources are
combined and procedures are applied in order to estimate the domestic transport flows on the
required level of detail.
Once the domestic transport data is available, it can be added to the O/D matrix. However, if all
domestic transport is added to the O/D matrix double countings are introduced because export
and import flows by sea with hinterland transport in the origin/destination country already
include domestic transport.
Document2
27 May 2004
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