Three major dimensions are of concern to depict the concept of modal competition.
The above figure depicts those three dimensions for two locations (A and B):
Modal choice competition is the most basic consideration in the modal
competition process. On the above example, three modal choice scenarios are
considered for two modes (orange and blue). The first two cases (1 and 2) are
instances where only one mode is used since it represents the most efficient
(or the only available) solution. This solution is derived by comparing the
two available modes and choosing the one that answers the best the requirements
of shipping freight or passengers between locations A and B. Case three represents
another possible solution where the two modes are used in a combination of two
segments with a point of transfer (red circle). This alternative is the classic
multimodal transport solution which is increasingly been applied over
transport systems. It enables to use modes over the segments they are respectively
the most efficient.
Infrastructure or route competition represents another dimension
where modal competition occurs over the usage of a specific infrastructure or
route. Three scenarios are generally possible. In the first case (4), there
is simply no competition as one mode has a monopoly over a route, either
because of technical (a subway line for instance) or regulatory (car-only expressways)
reasons. The second case (5) represents an exclusive sharing arrangement
where two modes are using the same infrastructure, but at different moments.
The issue of rail passenger and freight is a relevant example, as both are using
the same infrastructure but not at the same time. A decision has thus to be
made about which mode gets priority. In North America, priority is given to
rail freight while in Europe priority is given to rail passengers. The third
case (6) illustrates a situation where two modes have a mutual sharing arrangement.
Access to infrastructure is generally unconstrained but the total capacity is
obviously the result of respective levels of usage. Cars and trucks are commonly
sharing the same road infrastructure.
Market area competition is the third dimension of modal competition,
which is highly tied to geographical considerations. It mainly concerns transport
terminals that are drawing users and their associated flows, people and/or freight,
from their surroundings. In the above example, locations A and B have their
own exclusive market areas (light green and orange) over which that have a clear
advantage. Competition occurs over a portion of the territory where the respective
advantages of locations A and B are not clear (green); the competition margin.
Technical improvements have increased competition margins as terminals such
as ports are competing over overlapping market areas that may span whole regions.