• Introduction
• System Description
  • User Characteristics
  • Usage
  • User Response
• Assessment
  • Travel Impacts
  • Benefits
  • Costs
  • Equity
  • Barriers to Implementation
  • Conclusion
• Case Studies
• References

INTRODUCTION

Ridematching facilitates ridesharing (carpooling or vanpooling) by helping travelers find others with similar origins, destinations and travel times who are also interested in carpooling for regular or non-recurrent trips. Users access this information from the Internet, intranets and office computers, home computers, interactive telephones and pagers or simple paper match-lists.

Ridematching can be planned and executed on a daily or weekly basis for regular commute trips that are fairly consistent and do not change. Alternatively, ridematching can be dynamic such that an independent organization matches passengers with drivers for individual ad-hoc trips (as opposed to regularly scheduled trips), using telephone and computer technologies. Thus dynamic ridesharing differs from regular carpooling and vanpooling in that ridesharing is arranged for individual trips rather than for trips made on a regular basis and requests for ridesharing can be made close to the time when the travel is desired. (Casey et al., 1996)

"Dynamic rideshare matching differs from traditional rideshare matching in two important ways. The first major difference is the treatment of the traveler's schedule. Traditional systems assume the traveler has a fixed schedule and a fixed set of origins and destinations (Michalak et al., 1994). A dynamic system must consider each trip individually and be able to accommodate trips to arbitrary points at arbitrary times by matching users' individual trips. The second major difference is that dynamic ridematch systems must provide the match information to the user quickly to accommodate near-term (e.g. same day) travel as well as long-term (e.g. future days or weeks) trips. Traditional systems frequently provide a matchlist through paper mail, a process that may take more than a day (Puget Sound Council of Governments, 1988; Walbridge, 1995). For these two reasons, the requirements for dynamic rideshare matching are more demanding than those for traditional rideshare applications." (Dailey et al., 1999).

Ride matching services are provided by organizations such as CTS, Inc. in Los Angeles, and RIDES, in the San Francisco Bay Area. These organizations keep a database of subscribers, and generate several hundred ride-match lists every week. Their focus is primarily long-term users, that is, commuters interested in finding a carpool partner, more than just a ride every once in a while. Conversely, the emphasis of ITS ride matching systems is on dynamic ridesharing, although they also offer more long term services. This is achieved by automatically generating ride match lists upon request by interested parties. Potential partners are matched on the basis of information pre-recorded in the database, usually consisting of usual commute times, and residence and workplace locations.

SYSTEM DESCRIPTION

Three ride matching system field trials are reviewed here. One was conducted as part of the Los Angeles SmartTraveler Field Operational Test. The other was the Bellevue Smart Traveler, whose focus was primarily ridesharing, although it also provided traffic and transit information. The Seattle Smart Traveler provided dynamic ridesharing services via the web and electronic mail at the University of Washington in Seattle.

Los Angeles SmartTraveler
This test was a public/private partnership between the California Department of Transportation, the Los Angeles County Metropolitan Transportation Authority, the State of California Health and Welfare Data Center, Commuter Transportation Services, Inc., Pacific Bell and Pacific Bell Information Services, IBM Corporation, and North Communications. Funding for the field test was provided by the State of California, through the California Advanced Public Transit System Program, and by the Federal Highway Administration, through earthquake relief funds. In addition to ridesharing services, the field test included pre-trip information services.

The ridesharing service allows users to obtain lists of potential ride matches, via touch-tone telephone. Users must pre-register, which entails giving some personal information, including their usual commute times and preferred pick-up and drop-off locations. Upon request, the system can call the people in the list and deliver an user-recorded message. The ridesharing materials were distributed to 68,000 people.

Bellevue Smart Traveler
The BST project was led by researchers from the University of Washington, in partnership with TransManage and with participation from PacTel. The demonstration phase of the project took place between November 1993 and April 1994. The project was funded by the Washington State Department of Transportation and by the Federal Highway Administration.

The main purpose of the Bellevue Smart Traveler (BST) is to facilitate ridesharing (carpooling), but it also provides traffic and transit information. The ridesharing service operates by subscription: once registered, a participant is entitled to offer rides, and to accept rides offered by other subscribers. The system is available via telephones and pagers.

The field test tracked the supply and demand for rides over a five month period. Test participants were selected based on their residence location (all participants worked in the same office complex). Three ridesharing groups were formed, with membership varying from 8 people in the smallest group to 27 people in the largest.

Seattle Smart Traveler
The Seattle Smart Traveler (SST) tested a dynamic ridematching system using the Internet and electronic mail (e-mail) at the University of Washington in Seattle. The project was part of the Seattle Wide-Area Information for Travelers (SWIFT), a larger Intelligent Transportation System Field Operational Test conducted by the Washington State Department of Transportation, the University of Washington, King County Metro, and five private sector partners, with funding from the Federal Highway Administration.

The dynamic ridematching system was developed and operated at the University of Washington from 1995 to 1997. The system was designed by researchers in the Department of Electrical Engineering using a World Wide Web or Internet interface. A number of technologies and techniques were considered for the system. The combination of a Web Page on the Internet and e-mail was selected based upon availability to the target user groups. These systems are available on a 24-hour basis to students, faculty, and staff at the University. In addition, individuals in these groups tend to be computer literate and use e-mail and the Internet on a regular basis. The SST was designed to meet the needs of individuals interested in forming ongoing carpooling arrangements, as well as those interested in offering or obtaining a ride for a single trip. Two of the unique elements in the system design were accommodating the desired travel times and identifying origins and destinations.

To provide flexibility in the matching of trips, a time range or window was used for both the requested departure and arrival times. A search structure was developed using a series of pull-down menus allowing users to easily identify their desired origins and destinations from a search tree containing four levels of detail. Although the design of the SST was relatively complex, the system was easy for participants to access and use. A potential participant first accessed the Web site by entering either their student or staff identification number or user password. The individual then completed an SST application form, which included their telephone number and e-mail address, but not their home address. The participant could request a trip at the time they registered and on an ongoing basis. Three types of potential matches could be requested. These were regular commute trips, additional regular trips, and occasional trips. A user entered the origin, destination, day of week, departure time, and arrival time for each trip type they would like to check for a rideshare match. (Assessment of the Seattle Smart Traveler, FTA, 1999)

User Characterstics

Moreover, the city of Bellevue was considered a good site to try carpooling services, because it exhibits radial commuting patterns, as well as peak hour congestion: employment is concentrated in the downtown area, and workers' residences are located in the suburbs. It was found that approximately 2/3 of auto commuters have little knowledge of the availability of transit services to downtown Bellevue, or of its cost. But some commuters, especially low-income commuters, expressed interest in switching to transit or to carpool if more information was available about these alternatives.

Los Angeles Smart Traveler
Users of the Los Angeles SmartTraveler ridesharing service tended to have longer trips to work than the average Los Angeles County commuter, and were less likely to drive alone. Of all users, 18% used alternative modes to get to work about once or twice a week. Users stated that circumstances for which their regular commuting mode was not available are rare, suggesting that demand for occasional carpooling is likely to be low. Other factors that may lower the demand for carpooling are that half of those surveyed said they sometimes work a schedule different from their regular one, and that sometimes their work takes them to places other than their office. About half of all users felt they have access to good transit service. Most felt they needed transit and carpool information, yet at the same time most refused to ride with strangers.

Seattle Smart Traveler
Approximately 400 individuals used the SST dynamic ridematching system during the demonstration. The ongoing monitoring by University of Washington staff and the survey results provided the following information on SST participants:

• Faculty and staff comprised approximately 68 percent of the users, while students represented 32 percent. Student use increased in the fall and winter of 1996, however.

• The vast majority of the participating faculty and staff had regular work hours. The student’s schedules varied more by day of the week, but approximately 60 percent indicated fairly regular commute schedules.

• Most participants were regular users of e-mail and the Internet and most reported being able to access both systems at home and at work.

• Thirty-eight percent of the respondents normally commute by bus, while 37 percent carpool, 25 percent drive alone, and 5 percent bicycle.

• Thirty-five individuals said they would use SST for a match when their normal commute mode was not available, although most noted that they normally ask a friend for a ride.

Usage

Bellevue Smart Traveler
Over the five-month period of the demonstration project, 509 rides were offered and 148 rides were looked for using a telephone. Of these, on 33 occasions the caller requested more specific information about a ride offer. The system did not keep track of pager-based searchers. Users need not log when a ride match was found, as this function was optional. As a result, the system reported only six logged matches. It was later found that several people used their pager, instead of the telephone, to seek ridesharing information and traffic or transit information.

Self-reported usage is shown in Table 1. Users were more likely to offer than to take rides. There was also a large proportion of participants who actually did not participate in ridesharing activities: almost one half of all registered users never looked for a ride, while about 25% never offered a ride.

Source: Haselkorn et al., 1995.

Los Angeles SmartTraveler
Use of the ridesharing service appears to be seasonal: it increases on bad weather months. On average, the system logs 205 calls per week, far below the demand for ridesharing serviced by Commuter Transportation Services (CTS). In fact, although ARMS covers about 10% to 30% of the region covered by CTS, it receives roughly only 3% of the ride-match phone calls, and it generates only one match list for every 500 lists generated by CTS every week.

An intercept survey of callers (sample size=24) indicated that use is fairly irregular: 60% had used the system less than twice, and the vast majority were looking for a regular carpool partner, as opposed to a one-time ride. Only three out of the 20 people who attempted to contact those in their match list were able to arrange a ride.

An experiment was conducted to establish how successful the system was in finding occasional carpool partners. Fifteen "fictitious" people were registered in the ridesharing database, and each day for eight weeks, a researcher called to try to arrange a ride for one or two of them. The results of this experiment indicated that chances of getting a ride were about 20% when the user personally called each person in his/her match list, including some conditional offers. Thirty-six percent of those contacted did not return the call, 28% could not offer a ride that day, and 16% stated they would never offer a ride. These results confirmed users' suspicions that the database was not updated regularly enough, and that it was not large enough to support ridesharing. The automated message feature performed poorly: it could not be accessed half of the time, and it resulted in a no-response rate of 93%.

Seattle Smart Traveler
Use of the SST dynamic ridematching system was tracked by University of Washington researchers over the 15-month demonstration. In addition, two surveys were conducted during the last month of the test. First, an e-mail survey was used to obtain information from participants who had requested a rideshare match or who had been on a match list. Second, a survey on the SST Web Page allowed all participants to provide general comments on the system and feedback about the test.

Figure 1 highlights the number of registered participants in the SST. Approximately 400 individuals registered for the SST through November 1996, with the actual number of active participants varying over the course of the demonstration.

Figure 1: SST Use

Source: Assessment of the Seattle Smart Traveler, FTA, 1999

As illustrated in Figure 1, participation grew during the spring, summer, and fall of 1996. The largest number of active participants occurred in the spring and fall of 1996 when some 200 individuals were in the SST database. Figure 1 shows the periods at the end and the start of each quarter when the SST database was updated to eliminate individuals no longer wishing to participate. Although purging these individuals from the database reduces the total number of participants, and the potential pool of rideshare matches, it enhances the likelihood that possible matches will actually result in a successful carpool.

Figure 1 also includes the number of University of Washington students, faculty, and staff registered in Metro’s ridesharing program. There was only a 20 percent overlap of individuals registering for both programs, indicating that they served different clientele. University researchers also tracked the time of day participants accessed the SST. Approximately 20 percent of the system use occurred outside the normal business hours of 8:00 a.m. to 5:00 p.m.. As noted previously, one of the reasons for selecting the Internet for the test was the ability to access the system on a 24- hour basis.

A total of 2,065 trips were registered in the database over the course of the demonstration. Figure 2 presents the cumulative number of attempted matches, the cumulative number of successful matches, and the cumulative number of e-mail messages sent to form a carpool. Approximately 700 matches were requested. Of these, some 150 matches (21 percent) were established. The individuals requesting the match were provided with the names of potential riders. At least 41(about six percent) individuals actually established a carpool for the requested trip.

Figure 2: SST Matches

Source: Assessment of the Seattle Smart Traveler, FTA, 1999

User Response

Bellevue
The Bellevue field test included personal interviews, to learn about participants' opinion of the service. Several reasons were voiced about the inconvenience of ridesharing: uneasiness about getting into a stranger's car, busy and/or erratic schedules, complex lifestyles. Several people complained about offering rides and not receiving responses; as a result they became very discouraged. This was partially attributed to the fact that some of the ride groups were too small to sustain dynamic ridesharing activities.

Additional reasons mentioned for not forming carpools include:

• Never receiving calls from interested riders
• Never finding a ride at a convenient time
• Often rides were offered one way only
• Having an unpredictable work schedule

Participants thought that addressing the following issues would encourage carpool formation:

• Getting participants to know each other
• Knowing other participants' home location with respect to own
• Agreeing on predetermined pick up points
• Knowing participants' scheduled commute times
• Making the system more user-friendly
• Having HOV lanes on the route to work
• Making sure participants cleared a police check

Seattle Smart Traveler
As noted, approximately 400 individuals used the SST dynamic ridematching system during the demonstration. The ongoing monitoring by University of Washington staff and the survey results provide the following information on SST participants and their use of the system:

• Of the 141 participants responding to the e-mail survey in May and June of 1997, 31, or 22 percent, indicated that they did share a ride with someone as a result of using the SST.

• Forty-five individuals responded to the survey on the SST Web Page. This survey focused on the ease of use of the Web Page and SST system, normal commute modes, and general reactions to the test. The overall comments were positive related to use of the SST system. A few respondents suggested that the length of the forms and the process may inhibit some potential users.

• Thirty-five individuals said they would use SST for a match when their normal commute mode was not available, although most noted that they normally ask a friend for a ride.

• The SST may have been viewed by some potential users as too temporary or too experimental. As noted in Chapter Three, some of the news articles and information in the U-PASS brochure noted that the SST was a temporary program and that it was operated by researchers in the ITS program. These types of comments may have led some students, faculty, and staff to think of the SST as an experiment or research project rather than a ongoing service, and may have limited their participation.

• One limitation to ridesharing continues to be concerns about sharing rides with strangers. Although some of the features of the SST were designed to help address this concern, the system was not able to overcome this issue.

ASSESSMENT

The first dynamic ridematching projects, the Bellevue Smart Traveler and Los Angeles Smart Traveler, generated very low levels of matches. Participants were amenable to the dynamic ridesharing idea, liked the technology and presentation of information, but were unwilling or unable to form rides for a variety of reasons. Ridematching systems were initially limited by several factors including:

• The participant base was often too small to ensure sufficient matches.
• Projects were implemented a little before the real boom in Internet use.
• Technologies available at the time for developing dynamic ridematching systems were somewhat cumbersome.
• Initial projects may have been viewed by some potential users as too temporary or too experimental.
• Insufficient incentives to help promote ridesharing such as HOV lanes, parking incentives, and other techniques to encourage carpooling.
• Safety concerns: commuters were often reluctant to travel with strangers.

More recent dynamic ridematching projects, such as the Seattle Smart Traveler (SST), generated match and carpool levels that approximated the numbers of traditional rideshare programs. In fact, the SST was operated in parallel to a traditional, regional rideshare system for one year and the two systems were marketed to the user community on a side-by-side basis. The SST and the traditional system acquired approximately the same number of users, although there was little overlap in the user populations using the parallel systems. The project thus demonstrated that there was a user population (not reached by traditional methods) that could be reached using the Internet for dynamic ridesharing services.

As use of the Internet increases rapidly, new communication devices proliferate and congestion worsens, use of ridematching services could grow beyond the numbers achieved by traditional rideshare programs.

Travel Impacts

Ridematching has travel impacts to the extent that it encourages ridesharing. Rideshare programs which include incentives (parking reductions and HOV lanes) often reduce commute trips by at least 10% (Winters and Rudge, 1995). If implemented without such incentives travel impacts are often smaller. The most effective programs tend to have paid parking, subsidies for alternative modes, and other incentives to encourage reduced automobile commuting.

Because rideshare passengers tend to have relatively long commutes, mileage reductions can be relatively large. For example, if ridesharing reduces 5% of commute trips it may reduce 7% of vehicle miles because the trips that are reduced are longer than average commutes. Rideshare programs can typically reduce up to 8.3% of commute VMT, up to 3.6% of total regional VMT, and up to 1.8% of regional vehicle trips (Apogee, 1994; TDM Resource Center, 1996).

Benefits

• Congestion Reduction : Reduces peak-period automobile travel.
• Road & Parking Savings : Reduces peak-period automobile travel.
• Consumer Savings
• Transportation Choices : Increases travel choice.
• Road Safety : Reduces vehicle mileage, but increases vehicle occupancy, so crashes that do occur may have more casualties.
• Environmental Protection : Reduces automobile travel.
• Community Livability : Reduces automobile trips.

Costs

Cost data are available for the Los Angeles SmartTraveler field test only. Direct installation costs include development and marketing costs, while direct operational costs are primarily those of providing modem access and a phone line for data transfer. To estimate cost per use, it was assumed that each port costs $220 per month, and that it can service 150 calls per week (50% utilization rate); the phone line was estimated to cost $1.0 per use. Initial development costs were estimated at about $150,000.

Assuming a level of use similar to that experienced during the test, the ridesharing service would cost $110 per use for a one-year lifetime, or $27 per use for a five-year lifetime. This assumes no additional expenses for marketing and promotion. If installation costs are assumed to be sunk costs, then the cost per use would be approximately $3.

Costs to participants may include additional travel and time needed to meet rideshare partners, schedule constraints needed to match commuting times, loss of privacy, and restrictions on stops for errands.

                 Source: Giuliano et al., 1995

Equity Impacts

Rideshare matching services are usually open to anyone in a particular geographic area. Most ridesharing services are self-supporting. Most rideshare matching services are subsidized but the costs are usually modest, much smaller than the social cost of accommodating automobile travel. For example, if a ridematching service is effective at reducing just a few percent of automobile trips, its expenses can be paid through reduced road and parking facility costs. Rideshare programs generally increase vertical equity by improving travel options for non-drivers and making commuting more affordable (Source Victoria Transport Policy Institute, TDM Encyclopedia).

The chief barriers are:

• Lack of a large enough pool of travelers to form matches.
• Lack of appropriate incentives to help promote ridesharing (HOV lanes, parking incentives etc.)
• Reluctance of potential carpoolers to travel with strangers: a ridematching system that had a security screening process might help address this issue.
• Lack of marketing: potential users need to be informed of this option.

The effectiveness of ridematching projects can be enhanced by addressing the aforementioned barriers to implementation. Additionally, implementers should keep in mind that:

• Ridematching services should cover a large geographic area (such as an entire region) in order to create the largest possible pool of users.

• Transportation agencies, businesses and employees should all be involved in planning rideshare programs.

CASE STUDIES (including traditional rideshare programs)

These are excerpted from the VTPI TDM encyclopedia.

Commute Trip Reduction Rideshare Programs
Comsis (1993) and Pratt (1999) describe several successful rideshare programs, including the Commuter Transportation Services, which provides ridematching services in Southern California, an employment center ridematching service supported by businesses, a residential ridematching service provided to residents of a suburban community funded by a developer, and various vanpool programs.

Dynamic Ridesharing in Seattle (http://sst.its.washington.edu/sst)

Metro Vanpooling Program (http://transit.metrokc.gov)

Seattle’s Metro transportation agency provides ridematching services throughout the region and operates dozens of self-financing vanpools. Below are their instructions for organizing one:

You need four other people, in addition to yourself -- or as many as 14 -- to organize a vanpool. The more people, the lower your fare. Once your pool is together, you need to decide on a route, pick-up points and schedule. Choose a primary driver and at least one back-up. Primary drivers, who meet Metro requirements, ride free and may receive 40 free personal miles each month. Additional miles are available to drivers for a low mileage fee. Redmond Ride Sharing (www.ridequest.com),the Ridequest program in Redmond, Washington, is a computerized system for registering for ridesharing supported by the Greater Redmond Transportation Management Association and the City of Redmond. The program also has various promotional campaigns to encourage alternative transportation.Minerva Dynamic Ridesharing Service (Behnke, 1996)

The Minerva System uses cellular phones, palmtop computers, and wireless data communications to provide low-cost, door-to-door transportation in low-density areas and low travel corridors. The service can be integrated with conventional transit, paratransit and ridesharing services, plus consumer services such as home shopping, telebanking and e-mail, to help reduce the need for some trips altogether. The Oregon State legislature has committed $1.5 million to this project, with additional commitments of $3 million in matching funds from local pilot sites, and $1 million in in-kind support from private management consulting outfits. Fred Meyer's Vanpools: One-Stop Commuting

When the I-5 bridge over the Columbia River closed for repair in 1997, the Fred Meyers corporation established a vanpool program to help their employees get to work in Portland. The company leases 15-person vans, and pays all expenses (fuel, parking, etc.). Employees organize their own routes, schedules and drivers. There are currently 11 vanpools with 10 riders each. The vans pick up riders at a central meeting spot, usually a Park & Ride. Drivers may use the vans for personal errands after work, and vans are available during working hours for business meetings. The program coordinator reports “Vanpoolers have told me they love the program! It relieves their stress. They learn more about the company by riding with people in their departments. They relax before they get home. It’s reduced their [vehicle] insurance rates and cut their commute time in half.”San Francisco, CA

Approximately 8,000 to 10,000 people, or nine percent of total carpoolers, participate in casual carpooling in the San Francisco area. During the morning commute periods, pick-up points are in Oakland near Bay Area Rapid Transit (BART) stations and in Alameda-Contra County near Costa Transit bus stops. These sites serve as loading zones, provide users with a back-up choice if a ride is unavailable, and guarantee users a ride home in the evening. Drop-off points usually are near the Transbay bus terminal in downtown San Francisco, although other destinations are also common. These sites are centrally located and provide passengers with other means to continue their trip if needed. Carpoolers gain the benefit of a 10 to 20 minute timesavings while avoiding a $1.00 toll by using the HOV toll bypass lane; passengers save money. Until recently, there was no market for evening casual carpooling since there were no HOV lanes heading out of San Francisco. In 1999, a 20-mile HOV lane was constructed on I-80 and, with support from Environmental Defense organizing and securing destination signs in downtown San Francisco, limited evening casual carpooling has begun.