Trip characteristics

Travelers making regular trips each day, particularly for work or school, are more likely to take transit. Repetitive trips can be planned in advance to coordinate with transit schedules; some transit services offer discounts for regular riding; transit service is usually better during the rush hours, when these trips tend to occur; and there is more competition for the use of family cars when work trips are made. Mass transportation is less likely to be used for shopping and recreational trips because of the difficulty of carrying packages, the requirement to pay separate fares for each person in the group, and long waiting times and walking distances. Thus, transit use is much lower at midday, on evenings, and on weekends than it is during peak weekday periods.

Traveler and household characteristics

Among the most influential factors determining travel-mode choice are the characteristics of the travelers themselves and their households. These factors cannot be directly affected by public transportation policy, while service characteristics and even land-use patterns are subject to some control.

The availability of automobiles has a powerful influence on the use of transit, because the quality of automobile service is commonly superior to that of transit. Auto availability is a household characteristic, reflecting the interaction between the number of cars in the household, the number of drivers, and the travel needs of those drivers. The use of mass transportation is quite low in households having a car for every driver, except where one or more travelers make regular trips to congested areas where good quality transit is available. It is much higher in households with fewer cars than drivers. These are often lower-income households, and so transit usage is often correlated with low income. To compete with the automobile, transit service must be very good, and, where it is, the relationship between income and transit use may be reversed—i.e., higher-income travelers may use transit more.

Gender is an important determinant of transit use, with women traveling by transit more than men. Men may get priority use of the household car for work trips because they may be the primary wage earner and because women have traditionally been more involved in child care and household management. These gender roles are changing rapidly. Men may be the dominant users of some high-quality downtown-oriented transit services if their spouses work in suburbs where transit services are limited.

Alternative service concepts

In low-density settings, traditional fixed-route, fixed-schedule bus or train operations cannot meet market needs. If the priority is to discourage travelers from driving alone in their automobiles, mass transportation services can include a variety of forms of individualized ride sharing that put 2, 4, or even 10 people in a single vehicle. Some agencies provide rider matching services and better parking arrangements to encourage carpooling, the sharing of auto rides by people who make similar or identical work trips. Car-pool vehicles are privately owned, the guideways (roads) are in place, drivers do not have to be compensated, and vehicle operating costs can be shared. On the other hand, carpoolers must coordinate their travel times, which can be a major inconvenience.

Some agencies and employers have subsidized vanpooling, ride sharing in 8- to 15-passenger vans provided by the sponsor. One worker is recruited to drive the van to and from work in return for free transportation and limited personal use of the van. Passengers pay a monthly fee to the sponsor. Van pools are most successful for extremely long work trips (e.g., 30–50 miles each way).

The uncertainty associated with putting a new transit service into the marketplace, particularly in low-density suburban settings, has been avoided by selling subscription services. Workers with common origins and destinations buy monthly bus tickets in advance, for which they receive guaranteed seating and a commitment to be delivered to work on time, usually without intermediate stops. The subscription operator normally requires a minimum ridership level to assure financial viability of the route.

These unconventional transit services operate about as fast as a private automobile, but they allow many riders to share the cost, so the price to an individual is usually low. Their main disadvantage is that they do not give riders schedule flexibility. If there is a family need to go to work late or come home early, or a work need to stay after hours, the traveler may be stranded. Those who often require schedule flexibility avoid ride-sharing services. Some employers and transit operators reduce this obstacle by using backup vehicles to provide guaranteed rides home.

Low-density trip needs, and particularly the needs of the handicapped and elderly, have been met with demand-responsive services, in which vehicles are dispatched to pick up travelers in response to a telephone call. This provides door-to-door service, but if a vehicle serves several travelers at once, trip times can be very long; if it serves only one person (or group) at a time, the operating costs can be as high as taxi fares or higher.