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

modes, each with individual associated cost characteristics, were in-
cluded in the model.
The complete model was then cast in terms of a simultaneous equa-
tion system and a qualitative analysis was undertaken. This analysis
allowed us to investigate the effects of changes in system parameters
upon the equilibrium values of all the endogenous variables. It was
found that by making quite plausible assumptions concerning the signs of
simple partial derivatives we were able to unambiguously derive.the signs
of the resulting changes in solution values of the variables. It was
also shown that in many cases statements could be made concerning the
relative sizes of the effects. That is, we were able to show that a
five-cent increase in the transport rate for a certain mode would have
the same effect upon the quantities carried by the various modes and
shipper's costs as a five-cent increase in associated costs for that
mode. A complete listing of these theorems is contained in Table 3.2
In the three appendices to Chapter III we derived measures of re-
sponse for the transportation market. Appendix A contained a derivation
of the elasticity of transport demand in terms of the elasticities of
the product supply and demand curves. Appendix B showed the derivation
of the elasticity of the "demand" for a particular mode of transport.
This elasticity was presented in terms of the elasticity of the demand
for transportation and the elasticities of the transport supply and as-
sociated cost functions.
In Appendix C to Chapter III we investigated the implications of
allowing one of the transport modes to be composed of a single large
firm. This model, with its obvious reference to rail transport, views
this one, monopolistic, industry as competing directly with one or more
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