Schaller Consulting Archive
By Bruce Schaller
Principal, Schaller Consulting
The research reported in this paper was conducted while the author was Deputy Director, Marketing Research and Analysis, New York City Transit.
Presented at Transportation Research Board Annual Meetings, Washington, DC, January 1999.
Attracting customers to the bus and subway is an often-discussed goal for transit agencies. Current research methodologies such as travel demand, stated preference and discrete choice models and opinion research are sometimes poorly suited to determining which types of service improvements, facility designs or fare policy initiatives will be most effective in attracting potential customers. Drawing on elements of established methods, an approach is developed for use by New York City Transit, focusing on travelers' actual experience of the subway, bus, auto, taxi and car service and their reasons for mode choice. Survey questions were developed based on focus group findings that New Yorkers actively choose between competing modes based on six major factors, from how long the trip will take to availability of parking. Travelers choose the mode that presents the least difficulty for a particular type of trip. Survey results show that the areas of subway service improvement with the greatest potential ridership payoff are: reducing how long it takes to make a trip; increasing the availability or ease of use of transit; and making traveling on the subway a more comfortable and relaxing experience. Two external factors--parking availability and taxi fares--are also found to significantly impact subway ridership.
Finding cost-effective ways to increase transit ridership is a central goal for transit agencies. How can travelers be attracted to the bus or subway from auto, taxi and other modes? What prospective service improvements, facility designs, customer information, fare policies or other steps would make transit more attractive to customers? What is the importance of speed and reliability versus passenger comfort?. In the wake of a steep drop in the crime rate, how important is personal security to customers' travel choices? When is cost a major factor in mode choice? How important are transit service levels or fares compared with external forces such as traffic congestion, parking costs or taxi fares? What has been the impact of transit service improvements or changes in the fare? How should publicity be targeted toward the most likely new users?
Researchers can draw from a variety of methodologies to answer these questions. The appropriate choice depends on the type of information sought. The purpose of this paper is to develop and test a methodology that will address these questions for use in strategic planning and to set budget priorities.
In evaluating possible methodologies, it is critical to cover the full range of potentially fruitful areas so as to compare across different types of actions. Stated negatively, it is critical to avoid prematurely focusing on some types of service improvements to the exclusion of others.
The selected methodology should also facilitate tracking customer responses to service, fare or other changes. Tracking customer responses permits real-world testing of the effectiveness of policies as they are implemented. Finally, the approach should be practicable to implement given funding and logistical constraints.
This paper begins by identifying strengths and shortcomings of existing methods to gauge the impact of service and fare changes on transit ridership. A survey methodology is then developed that is intended to help guide strategic planning, priority-setting and service planning at MTA New York City Transit. Finally, results from over 2,000 telephone interviews with New York City residents are presented, with implications for further research and the validity of this approach.
APPROACHES TO IDENTIFYING SERVICE PRIORITIES
Research methodologies to identify sources of ridership growth fall into three main groups: (1) travel demand modeling; (2) stated preference and discrete choice models; and (3) opinion research. These established methodologies are suitable for a variety of planning and budgeting purposes. For example, modeling can gauge the ridership payoff of defined levels of service such as different travel times, service frequencies or fares. Opinion research, on the other hand, provides a wealth of customer feedback on the strengths and weaknesses of particular aspects of bus, subway or other services.
These approaches have difficulty, however, guiding overall priority-setting for budgeting and strategic planning where the relevant question is which of a wide variety of possible actions will most effectively build ridership. This question entails looking across a range of possible service improvements rather than a limited number of pre-defined options. It also entails evaluating "soft" factors like personal security and comfort which by their nature lack measurable service levels and thus are difficult to assess with formal models.
After briefly reviewing the strengths and shortcomings of existing methods, a somewhat different approach, combining selected aspects of modeling and opinion research, is developed to meet strategic planning and budgeting needs.
Three Approaches To Ridership Analysis
Travel demand models
Travel demand models forecast household travel behavior taking into account land use, household socioeconomic characteristics, travel costs and levels of service. (1) (2) (3) With mathematical rigor, the models quantify the importance of these influences on travel choices and the impacts of policy choices. A well-developed model can pinpoint the marginal change in ridership from incremental, real-world changes in travel time, service frequency and other inputs.
Primarily used by metropolitan planning organizations for travel demand management and land use planning, the breadth, sophistication and attendant complexity and expense of travel demand models can be drawbacks given the more focused needs of transit agencies. These models also typically cover only major transit service-related factors such as transit access, travel times and service frequency. (4)
Stated preference and discrete choice modeling
Stated preference and its cousin, discrete choice modeling, are perhaps the most frequently-chosen method to project the effects of service and fare changes. In both methods, survey respondents are presented with several transportation options and asked which option they would choose. By varying the frequency of transit service, travel time, crowding, fares, tolls, parking costs, etc., researchers can estimate ridership for different combinations of attributes. The transit agency can then develop a service configuration that best meets cost-effectiveness and ridership objectives.
The main advantage of stated preference and discrete choice modeling is their focus on traveler response to various options. (5) The analysis can include whatever attributes are of interest, unconstrained by whether survey respondents have ever experienced such services, fares, costs etc. Surveys are readily carried out in a reasonable timeframe and cost and do not require the advanced expertise essential for demand modeling.
Major shortcomings of stated preference and discrete choice models limit their utility, however. These models typically overstate actual usage of new or improved transit services, often by large amounts. Analysts can apply discount factors to reduce projected ridership to more credible levels, but the lack of validated discount factors makes this an inherently uncertain process. More fundamentally, it is not clear that responses to alternative service configurations are meaningful. At times, respondents appear to be saying "yes, yes, yes" to the basic idea of having available a particular type of service regardless of the particular bus or subway headways, travel times and other salient details of each option.
A second serious problem is that these methods are best-suited for testing well-defined attributes that are within respondents' range of experience, such as fares and frequency of service. It is difficult to describe to respondents non-quantifiable attributes such as levels of personal security, reliability of service or facility aesthetics. In New York City, these can critically affect mode choices.
Finally, the design of stated preference and discrete choice surveys requires identification up-front of an appropriate list of possible service changes. This is a tricky process, for in narrowing the list to a manageable number of items to investigate, researchers may unintentionally exclude effective measures.
Increasingly over the past decade, transit agencies have turned to opinion research to obtain consumer reaction to transit services.(6) Surveys show customer satisfaction levels, ratings for different aspects of bus and subway services and ways to group or "segment" customers based on travel behavior and socioeconomic or other characteristics. (7) Results of this work yield a rich array of information showing areas of satisfaction and discontent and the needs of various groups. A main shortcoming of satisfaction surveys, however, is that satisfaction levels do not necessarily predict behavior. The experience in New York City is that individuals' subway and bus ridership correlates poorly with both overall satisfaction levels and ratings of major service attributes such as speed of travel, reliability of train or bus arrivals, personal security, etc. Ratings do not explain actual ridership because they do not show which factors drive mode choices.
Transit agencies also use qualitative research techniques such as focus groups and one-on-one interviews. These open-ended, discussion formats provide a rich, in-depth understanding of customer opinion. They are particularly valuable for new or complex topics where customer views are not understood, and thus aid in planning survey work by providing appropriate approaches, question wording and response categories. Qualitative methods are also highly useful when reaction is needed to visual or aural stimuli such as signage, customer communications and radio or television advertising or to physical facilities such as subway stations, subway cars and buses.
By their nature, however, focus groups and individual interviews do not provide quantification of behavior. In addition, a series of studies in different areas-station design, customer information, route changes, etc.-leaves one without the means to compare the potential ridership response of one type of change with that of another.
Formulating an Approach to Meet Strategic and Service Planning Needs
Given the issues with established methodologies, an approach was developed that combines selected aspects of these methods in a fashion tailored to identify service priorities to meet strategic business and service planning needs. The key elements drawn from existing approaches are:
The remainder of this paper summarizes the development of this method and presents survey results and implications.
The Mode Choice Decision Process
The key to ridership growth analysis is understanding travelers' choice of mode. What most affects travelers' decision to use transit versus other types of transportation?
Mode choice is typically conceptualized as a two-step decision process involving (a) identifying a choice set and (b) applying some type of decision rule. Literature on decision protocols identifies a wide variety of decision rules that customers could possibly employ. (1) These range from overall satisfaction with each mode (e.g., Ms. Jones is very satisfied with the auto and somewhat satisfied with travel by local buses, and so chooses the auto) to evaluation of modes on specific criteria. Travelers using criteria may make their choice based on a dominant criterion or some blending of ratings. Criteria themselves can vary from the benefits of each mode (cost, travel time, etc.) to lifestyle considerations (desire for independence, brand identification) or externalized concerns (saving energy or reducing pollution).
Qualitative research was conducted to garner a detailed understanding of how New York City residents choose among the numerous types of transportation available to them. In a series of eight focus groups, participants were asked their overall view of the subway, local bus, auto, taxi and car service; likes and dislikes of each mode; mode preference and reasons for their choices. Participants were segmented into seven customer groups based on age and current usage of transit and non-transit modes.
The qualitative research found that (8):
Travelers actively choose among competing modes.
Few customers are wedded to one mode; most either use or actively consider using two or more types of transportation for a given type of trip. This is true for both discretionary trips and routined travel such as work-related trips. Customers are familiar with their choices, mainly from first-hand experience. And most importantly, customers readily articulate their options, their choice and the reasons for it.
Customers seek to minimize problems.
Customers make a finely-tuned evaluation of up to a half-dozen criteria to decide which mode presents the least cumulative difficulty. Which choice presents the least problem, on the whole, provided that none of the problems is unacceptably severe? This is a process of managing problems down to acceptable levels. In some situations one issue is dominant-e.g., the taxi is more expensive but at late hours safety concerns rule out the subway. In other situations a mix of factors are weighed-e.g., my car is more comfortable but how much will parking cost and will I get stuck in traffic?
A common set of utilitarian criteria are used in making travel choices.
How fast will the bus, subway or car take me to my destination? Is it safe? If I drive, can I find parking? What is the cost? A fairly small list of practical considerations are almost universally the basis for travel choices. In deciding how to travel, New Yorkers give little heed to how well a given mode comports with their self-image or to external considerations such as effects on the environment.
Mode choice is situational.
Travelers have different needs and concerns for the trip to work than for personal travel. Speed, reliability and convenience are the main concerns for getting to work in the morning. For personal travel, particularly at night and on the weekend, comfort, privacy and a "change of pace" enter the picture. (The differing criteria between mode choice for work trips and personal travel shed light on why satisfaction ratings correlate poorly with mode choices. Overall ratings for speed of travel, safety, etc. mask the effect of different situations-e.g., the subway is judged to be much safer and faster during the day than at night. Overall ratings also mask the varying importance of attributes-comfort is more important for personal travel than for getting to work.)
Measuring Reasons For Mode Choices
Survey questions were developed based on the central qualitative finding that customers attempt to minimize problems in choosing their type of transportation. Respondents are asked to indicate the frequency of problems for either work-related or personal trips-e.g., "How often is how long the trip will take a serious problem that affects whether you take the subway for work-related trips?" "How often is availability of parking a serious problem that affects whether you take the auto for personal trips?"
Each respondent is asked about the essential problems identified in the qualitative research for each of two modes. The first mode is simply that used most often for either personal trips or work-related trips. The computer-assisted telephone interviewing system selects a second mode from among those the respondent says he or she sometimes takes or considers taking for the same type of trip. The alternate mode is chosen to maximize the incidence of transit/non-transit comparisons, e.g., where bus is the primary mode and subway and taxi are alternate modes, respondents are asked about the choice between bus and taxi instead of between bus and subway.
After identifying the frequency of problems for primary and alternate modes, respondents are then asked for the most important reason to choose the first mode over the alternate mode (e.g., bus over taxi), and the most important reason for choosing the alternate mode over the first mode (e.g., taxi over bus) when taking the alternate mode.
This set of questions has a variety of advantageous features. The simplicity of the questions means that respondents across socioeconomic groups can readily and meaningfully answer the questions. Second, results can be easily explained to a variety of audiences. Third, this approach focuses on items of interest to NYC Transit including "soft" factors like personal security, and quantifies the relative importance of key factors for the mode choice decision.
Finally, this research could be cost-effectively integrated with ongoing data gathering by NYC Transit. Mode choice questions were added to the telephone interview portion of the NYC Transit Transportation Panel Project. The Transportation Panel is an ongoing survey of 1,500 New York City residents who complete a two-day mail-back travel diary and then a 15-minute follow-up telephone interview covering attitudes, demographics and special topics. As part of the Panel telephone interview, mode choice results can be tracked to discern the effect of service or fare changes, and can be tabulated against responses to opinion, travel and demographic questions.
The first section of the mode choice questions measure how frequently travelers encounter serious problems with each mode. Substantiating results from the focus groups, speed of travel is troublesome for all types of transportation. "How long the trip will take" is a serious problem "most" or "some" of the time for 40% or more of the travelers using every major mode-subway, bus, auto, yellow taxi and car service. (See Table 1.) As reflected in focus group comments, complaints about "how long the trip will take" encompass speed of travel, waiting time and reliability of service. Commenting on reliability, for example, one focus group participant stated, "The worst negative [about the subway] is the opposite of the most positive - when there are delays and you can't get to where you're going."
Beyond the common frailty of variable travel times, each mode evidences a different Achilles heel. How best to trade off one mode's deficiencies against its competitors' shortcomings is the central dilemma for mode choice decisions.
Subway: Not surprisingly, the subway's biggest problems are personal security and lack of comfort. As one focus group member said, "I think that's a real problem. Security. There's been a lot of muggings. I've had a lot of personal experiences where people have told me about situations where they've gotten mugged and they've gotten attacked."
Lack of comfort or ability to relax includes crowding, the discomfort of narrow seats and problems with announcements. The latter issue is illustrated in several focus group comments. Said one participant: "I think the public announcements are unreal. They're inaudible. They're basically annoying. I don't even try to listen any more." Another stated: "Sometimes they do not give you advance notice that they're going to go express, a local train deciding to go express. They wait until the doors close, and say oh, we're going express."
Auto: Sixty-six percent of auto users say that availability of parking is a problem most or some of the time. Parking availability is an issue of not readily finding parking at an acceptable price. One focus group participant recounted a vivid experience. "I drive into Manhattan under duress. I've driven in a couple of times, and I refuse to pay the parking prices in Manhattan. There are a couple of times where I've driven in, searched and searched and gone back."
Yellow taxis and car services: Cost is the most significant problem for taxis and car services. (Car services are a taxi-like service that provides pre-arranged, door-to-door trips, primarily in sedans and primarily outside the Manhattan core.) In the focus groups, participants weighed whether the higher cost of a taxi was worth the gain in speed and personal security.
Bus: The bus' only major problem is slowness, attributed to congested traffic and bus bunching: "The time that elapses between buses. Sometimes you wait for a bus for a long time, and then you have two or three of the same buses together."
Main Factors in Mode Choices
Customers' attempts to manage these problems down to acceptable levels in selecting a transportation option is evident in the reasons for their choice between the subway and its major competitors-auto, taxi, car service and the local bus.
Subway vs. auto. Twenty-three percent of respondents say they primarily use the subway for work or personal travel but sometimes use a car, or vice versa. Travelers decide between auto and subway based on travel time, availability of parking, comfort and ability to relax, and whether they can reach their destination using that mode. (See Table 2.)
Each of these factors is the most important factor for choosing between auto and subway for 20% to 33% of respondents with the exception of parking. Over one-half of those who primarily use the auto cite availability of parking as the main reason for sometimes taking the subway. Similarly, for 38% of subway-primary travelers parking is the main reason to stick with the subway. A focus group participant pinpointed the dominant effect of parking: "If you're going to go any place other than Manhattan, take the car. Comes the weekend, if you don't want to get frustrated trying to find a place to park the car, I'd still go into the City by subway." In sum, the availability of parking (or lack thereof) is a particularly important factor in the choice between the subway and auto.
Subway vs. taxi/car service. Ten percent of respondents use the subway as their primary mode for work or personal trips and use yellow taxis or car services as an alternative mode. The subway's lower cost is the main reason to make it one's primary mode; cited by 53%. (See Table 3.) A second important factor is travel time, named by one-third of subway users who sometimes use taxis or car services. (Note that for a number of trips, such as trips between Midtown and Downtown Manhattan during midday, the subway can be substantially faster than a cab or auto.)
Subway customers switch to taxis primarily when they feel a cab will be faster (38%) or when they cannot reach their destination by subway (29%). Car services are used primarily when the subway does not reach the destination (37%) or the trip will take too long by subway (28%).
Subway vs. bus. New York City's subway and bus services are in some respects complementary services serving different origin and destination pairs (i.e., trips taken on most crosstown routes in Manhattan and most bus routes in the other boroughs could not be made conveniently by subway). The bus and subway also offer a choice of transit modes where major routes overlap, such as on north-south avenues in Manhattan and some major arterial streets in the other boroughs.
This duality of being sometimes complementary and sometimes offering a choice is reflected in the major reasons for choosing the bus versus the subway. One major basis for this choice is "not being able to get there," indicating that the bus provides convenient routing but not the subway, or vice versa. (See Table 4.) "Not being able to get there" is a particularly significant reason to switch to the bus or subway as a secondary mode.
Where their routes overlap, subway and bus can also offer a tradeoff between speed and comfort. Travel times are the most common reason to choose the subway as either a main mode (55%) or an alternative (45%). Likewise, being more comfortable and able to relax is a major reason to choose the bus as a main mode (30%) and a frequent reason for subway users to opt for the bus occasionally (24%). A focus group comment illustrates the point: "The only time that I would take a bus would be coming home from work when I just feel like not traveling with crowds. It takes longer, but it's more comfortable."
Finally, travel time can favor the bus when it provides a more direct, faster service than the subway-e.g., for crosstown travel in Manhattan.
Whither personal security?
Notably, while personal security is a frequent problem with subway service it is only infrequently named as the most important reason to avoid the subway. The reason for this seeming contradiction is that personal security concerns are focused on evening and late night trips. Customers' sense of personal security during the day has improved greatly over the past decade due to lower crime rates, cleaner and renovated stations and fewer panhandlers. For trips made during the day-the majority of trips-personal security is still a concern, but a manageable issue rather than the prime factor in deciding whether to take the subway.
Implications for service priorities
Results from the mode choice questions identify the areas of subway service improvements with the greatest potential ridership payoff. The high-payoff areas are: reducing how long it takes to make a trip; increasing the availability of transit service; and making trips more comfortable and relaxing. Parking availability and taxi fares also significantly affect whether customers take the subway, auto or taxi.
Some of these results can be readily translated to strategic planning and budget priorities. The mix of operational considerations affecting "how long it takes to make a trip" are well-known. A variety of steps are underway to improve service in this respect. These include adding service in response to growing ridership; new capacity through the opening of the 63 Street tunnel; improving the reliability of service through new cars, installation of train-control systems using real-time information to prevent long waits between trains; and increasing speeds on the subway by modernizing signals and other means.
"Not being able to get there" covers a variety of situations, some of which can be addressed and some of which probably can not. Some trips, of course, are simply too far from subway and bus lines to be feasible by transit. But given the extensive subway and bus network, it is clear that "not being able to get there" can mean that using the subway or bus for the trip involves an unacceptable amount of time or hassle. Trips that are theoretically possible can be impractical due to multiple transfers; unfamiliarity with routes, stations and connections; or simply long distances. The popularity of free intermodal transfers between buses and subways, instituted in July 1997, has shown that making the transit system easier to use improves customers' sense of the availability of service.
The universe of trips served by transit can also be increased via operational steps such as changing subway or bus routing to reduce the need to transfer and increasing the frequency and reliability of service. Another promising area is to give customers information on the arrivals of next trains, delays, etc., that empower them to choose the fastest route and minimize the psychological impact of waiting times. Programs in the works to provide real-time train and bus information are moves in this direction.
While the idea of relaxing on the New York City subway may seem to be an oxymoron, comfort can be significantly improved. New subway cars, now on order, will have seats designed to accommodate New Yorkers' varying sizes, fewer poles blocking flow through the train, wider doors and intercom systems to contact the subway crew in an emergency. Station rehabilitations can transform dark, dingy stations into inviting, well-lit spaces that are easier to navigate. Installation of automated farecard sales machines can free up station agents to assist travelers exploring new routes. Other steps discussed with respect to reducing travel times, such as increasing frequency and reliability of service, also serve to reduce crowding and improve comfort.
The impact on subway ridership of the cost of parking and taxi fares underscores how decisions by municipal officials who control parking supply and set taxi fares affect the transit system. Parking availability is particularly important to move auto users into the subway.
Mode choice results are also useful for guiding marketing decisions. It is clear from this research that themes of speed, comfort and ability to go where you want to will strike responsive chords in subway customers and potential riders.
Does the methodology presented in this paper offer anything new? Are the same results obtained through established methods critiqued earlier?
Not surprisingly, the focus on the speed and reliability of subway service echoes the findings of earlier research. For example, an analysis of satisfaction ratings found that improving customers' ratings for "trains arrive at regular intervals," "speed of travel" and "gets you there on-time" would most effectively improve overall satisfaction with subway service.  An analysis studies across the country found that "travel time implications of travel alternatives are a highly important determinant of consumer choices." 
Previous studies also found that improving comfort would attract more travelers to transit   and that comfort, convenience and downtown parking costs are critical determinants of mode choice. 
Unlike previous studies, however, the results presented here show the importance of increased "availability" of transit service. Clearly, additional research is needed to flesh out the aspects of subway service that would make it seem more available to potential customers. Likely aspects include routing changes, reduced transfers, entirely new services and better wayfinding signage. Though there is a need for further research, this finding highlights the importance of availability and gives a clearer perspective on what has often been considered a marginally important "soft" side of service delivery.
The findings presented here also show that personal security ranks lower than travel times, comfort and availability as a determinant of mode choice, particularly for daytime trips. This finding was not necessarily expected, and is quite significant.
From a purely methodological standpoint, the approach developed in this paper demonstrates several important advantages over established alternatives. It is a simple, easily understood approach and can readily be integrated into an existing telephone survey. The question sequence is neither long nor onerous to respondents and produced credible responses. The approach successfully examined both "hard" service attributes such as travel times and fares and "soft" aspects such as personal security and service availability. Finally, the methodology is suitable for use in tracking studies, which promise to show how service, fare and other changes affect travelers' behavior. It thus seems to be a worthy addition to existing methodologies available to those interested in increasing transit ridership.
|Mode:||Subway||Bus||Auto||Yellow taxi||Car service|
|Frequency of problem:||Most of time||Most or some of time||Most of time||Most or some of time||Most of time||Most or some of time||Most of time||Most or some of time||Most of time||Most or some of time|
|How long trip will take||16%||48%||17%||51%||14%||42%||15%||49%||13%||40%|
|Comfort and ability to relax||17%||52%||10%||36%||11%||31%||10%||36%||7%||29%|
|Not being able to get there by (mode)||12%||38%||10%||37%|||||||||||||
|Availability of parking||||||||||37%||66%|||||||||
Yellow highlights problem occurs "most of the time" for at least 20% of respondents and/or "most of time" or "some of time" combined for 40% or more of respondents.
"" indicates attribute not asked for this mode
*Total number of respondents is 2,051. Each respondent is asked problem incidence questions for the mode he or she uses most often and for an alternate mode.
|Primary mode:||Subway (1)||Auto (2)|
Main reasons for choice:
|Availability of parking (38%)||Comfort/relaxing (33%)|
|Not able to get there by auto (20%)||How long trip will take (26%)|
|How long trip will take (17%)||Not able to get there by subway (18%)|
|Alternative mode:||Auto (1)||Subway (2)|
Main reasons for choice:
|Not able to get there by subway (30%)||Availability of parking (57%)|
|Comfort/relaxing (27%)||Not able to get there by auto (17%)|
|How long trip will take (14%)|
|Primary mode:||Subway (1)|
Main reasons for choice:
|How long trip will take (32%)|
|Alternative mode:||Yellow taxi (1)||Car service (1)|
Main reasons for choice:
|How long trip will take (38%)||Not able to get there by subway (37%)|
|Not able to get there by subway (29%)||How long trip will take (28%)|
Note: sample size is too small for comparison where taxi/car service is primary mode and subway is alternative mode. (1.5% of respondents fall into this group)
|Primary mode:||Subway (1)||Bus (2)|
Main reasons for choice:
|How long trip will take (55%)||Not able to get there by subway (31%)|
|Not able to get there by bus (21%)||Comfort/relaxing (30%)|
|Alternative mode:||Bus (1)||Subway (2)|
Main reasons for choice:
|Not able to get there by subway (37%)||How long trip will take (45%)|
|Comfort/relaxing (24%)||Not able to get there by bus (40%)|
|How long trip will take (22%)|
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