Chapter 12, Problem 1P

To determine

The description of the two basic demand forecasting situations in transportation planning.

Explanation of Solution

Introduction:

The number of vehicles or persons per unit time under a set of given land-use, socioeconomic, and environmental conditions that are expected to travel on a given transportation system are expressed as the travel demand.

In transportation planning, there are two basic demand-forecasting situations.

1. One situation involves travel demand studies for urban areas
2. Second situation deals with intercity travel demand.

The first one forecasts, was developed in the 1950s and 1960s, and it requires extensive data which can be prepared by surveys such as home interview or roadside interview. The information collected by these surveys provides useful information of the trip maker such as age, income, sex, mode of travel, auto ownership etc.

Data gathered about travel characteristic can be further aggregated by the zone for formulating the relationships between the variables and then for the calibration of various models.

The second demand forecasting situations gathers data on a larger extent than for the first one. The intercity travel collects data such as city population, average city income, and travel time or the travel cost between different cities.

Conclusion:

Thus, there are two basic demand-forecasting situations in transportation planning. The first one deals with the travel demand studies for urban areas, and the second one involves intercity travel demands.