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From: =?iso-8859-1?Q?Darb=E9ra?= <[log in to unmask]>
Subject: urban transport models and economic surplus
Dear list members:
I am sorry to admit it, but I do not know exactly how classical four steps
urban transport models can be used to measure the economic benefits of
various transport schemes at the agglomeration level. In other words, how
to derive changes in the economic surplus of the transport system users
(car and transit riders) brought about by changes in the transport supply
To my understanding, even when they work with constant margins, i.e. when
generation is given and the total number of trips is fixed, these models
allow for some implicit demand elasticity, imbedded in the distribution,
modal split and assignment equations. With proper feedback loops, these
models deliver, for the various policy alternatives tested, a reasonable
estimate of variations in the total generalized cost (expenditure and time)
and of variations of the total passenger-km travelled. Are these two the
paramerters to be used for measuring changes in the economic surplus? How?
Any suggestion for further readings?
Appoligies for my approximate English.
Richard DarbThetara
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Richard DarbThetara
LATTS
Ecole Nationale des Ponts & ChaussThetaes
6-8 Avenue Blaise Pascal
Cite Descartes
F77455 Marne la Vallee Cedex 2
FRANCE
Tel. O1 64 15 38 34 (international 33 1 64153834)
Fax O1 64 15 36 00 (international 33 1 64153600)
e-mail [log in to unmask]
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