encyclopedia

DEMAND

1. The quantity (of transportation) desired. 2. In an economic sense, a schedule of the quantities ((of travel) consumed at various levels of price or levels of service offered (by the transportation system). (TRB)

DEMAND ANALYSIS

A study of the factors that affect demand, performed by collecting data and using various analytical techniques to understand demand. (TRB)

DEMAND CURVE

The quantities of a given product or service that people are willing to purchase as a function of its given unit cost. (TRB)

DEMAND FORECASTING MODEL

A model that relates the amount of travel and price of the transportation service and the socioeconomic characteristics of the potential traveler. (TRB)

DEMAND MODEL (DEMAND-FORECASTING MODEL)

A model that relates the amount of travel to the level and price of the transportation service and the socioeconomic characteristics of the potential traveler. (TRB)

DEMAND MODEL, AGGREGATE

A model calibrated by combining observations of travel by individuals into geographic or demographic units that are used to estimate new flows when service attributes or unit sizes change. (TRB)

DEMAND RESPONSE

A transit mode comprised of passenger cars, vans or class C buses operating in response to calls from passengers or their agents to the transit operator, who then dispatches a vehicle to pick up the passengers and transport them to…