It is in everyone's best interest to understand the underlying assumptions whenever findings or conclusions are drawn from analysis. It helps to state the assumptions as clearly as possible because they inevitably presuppose conditions, etc. that may, or not be present or apparent to all. This is especially true during the initial development and definition of a project. Clients quite often have assumption that are at odds with yours.
Listing assumptions is also a useful part of the analysis because it will indicate the state of the variables that could effect the outcome, but that have been given fixed values, or ignored as being unimportant. Statement of assumptions also tends to overcome the objections to what has or has not been included in the analysis. Some common assumptions for transport (and similar types of) analysis:
a. A Closed system will describe the portion of the universe selected. Therefore Conservation, Superposition, Continuity, Laws of Nature will provide a basis for data collection, analysis, and modeling.
b. A set of consistent accounting rules will be used to provide the basis for financial and economic assessment.
c. A knowledge of and Operation within the local laws of the locality, nation, and international jurisdictions
d. Progress and improved human standards are desirable.
e. Mostly Peace, Political and Economic Stability.
f. General technological progress will prevail.
g. There are 'Limits' to growth and to aspects of technology.
h. Mostly Rational Decision making.
i. Reasonable Environmental Protection will be assured.
j. Safety and Security will be important priorities.
k. There will be some level of human error involved in operations
l. There will be some level of deliberate or inadvertent sabotage.
m. Some level of dishonesty will be present.
n. Some levels of corporate and personal greed will be present.
o. Some of the goals and objectives will conflict.
p. The individuals involved will weigh the goals and objectives differently.
This list is not intended to be exhaustive or optimally stated. It should however provide a beginning for a list for your particular project.
End to date: 060321, ams