Q2 Z2,(Q2) Z2(Q2) - Institute for Water Resources - U.S. Army

the respective modes of transport, we were able to treat these dif-
ferent modes as perfect substitutes. This allowed us to view the
shipper's choice of mode decision as a simple problem of cost minimiza-
tion. Emphasizing at all times the interdependencies within the market,
we were able to investigate the conditions under which a modal split
may occur and to derive the "demand curves" confronting the individual
modes.
In Chapter I we reviewed the structure and functioning of a traria-
portation market. Possible reasons for investigating the workings of
such a market were also discussed. The best of the current economic
models of the transportation process were classified as basically "multi-
market single-mode transport models." These models have probed deeply
into the relationships between product demands and supplies and trans-
port demands. .However, these investigations have been possible only
by almost completely ignoring the supply side of the transportation
market. Our "two-market multi-mode transportation model" was then pro-
posed as the next step in the development of a full multi-market multi-
mode model of transportation.
Chapter II contained a review of the transportation literature.
In a rather thorough review of the theoretical literature we traced the
major steps in the development of transportation models from 1838 through
1964. It was found that these studies have become increasingly con-
cerned with the case where many markets are served by a single mode of
transportation, or several modes displaying quite simple supply attri-
butes. Selected recent empirical works were .then reviewed. These works,
in contrast with the theoretical studies, were concerned with determining
quantities carried by different modes of transport. In constructing a
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