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This article is an analysis of frequency and convenience of transit for overnight service.

As noted in an earlier blog post, in November and December 2016, the Office of Performance Management and Innovation, in collaboration with municipal and advocacy partners, surveyed potential passengers about their current overnight travel patterns and their preferences regarding a potential overnight bus service. The data has since been released to aid the design of overnight service proposals.

Respondents for the overnight survey were not randomly selected, so results cannot be generalized and demand cannot be estimated from their responses. The overnight survey does, however, provide unique insight into the stated preferences of potential passengers with regards to several questions that cannot be answered with our other data sources. Such questions include how potential passengers’ optimal boarding times relate to other characteristics of their travel and what service levels would have to be provided in order for potential passengers to use overnight buses. This blog post discusses some of the most interesting findings regarding the likelihood of use, optimal boarding times, and service level tolerances of respondents.

We analyzed respondents divided by the purpose for which and by the frequency with which they currently travel overnight. We looked at travelers with the following characteristics:

  • A work traveler is defined to be any respondent who said that their trip began or ended at work. 
  • Worker travelers were then further divided into two categories for some analysis: those leaving a non-work location (usually their home) to go to work, and those leaving a work location (usually to go home.) This was done because there are significantly more workers leaving work than those going to work in our sample, so the behaviors and preferences of travelers to work can be outweighed unless they are isolated from the rest of the sample.
  • A recreational traveler is defined to be any respondent who said that their trip began or ended at a social or recreational location and who did not start or end at work. 
  • Frequent travelers are respondents who currently travel three or more times per week, semi-frequent travelers are respondents who travel one or two times per week, and infrequent travelers are respondents who travel less than once per month. 

Likelihood of Use

The frequency with which travelers begin trips between 1AM and 5AM is highly correlated with how likely they are to use an overnight bus service. The purpose for which they travel is not.

Respondents were asked: “If a safe and affordable night bus service were available between 1AM and 5AM, how likely would you be to use it?” Respondents who currently travel more frequently are more likely to say that they would use an overnight bus service if it were available. For work travelers, 81% of frequent travelers, 60% of semi-frequent travelers, and only 39% of infrequent travelers said that they were extremely likely to use an overnight bus service. For recreational travelers, 83% of frequent travelers, 53% of semi-frequent travelers, and only 31% of infrequent travelers said that they were extremely likely to use an overnight bus service.

The correlation between travel frequency and likelihood of use is much stronger than the correlation between travel purpose and likelihood of use. It would be reasonable to expect that workers would be more likely to use overnight an overnight bus than recreational travelers would be. Work travelers are likely to have less flexibility in canceling or rescheduling their trips, and recreational travelers may be more likely to have the resources to afford alternative forms of travel (such as a ride-sharing service.) However, after controlling for the frequency with which respondents currently travel overnight, there is no statistically significant* difference in the self-reported likelihoods of using an overnight bus service between workers (who make up 30% of travelers) and all travelers or between recreational travelers (who make up 58% of travelers) and all travelers. This is surprising because it suggests workers are actually no more likely to use overnight buses.

It is important to note that in the dataset of responses, most work travelers currently travel frequently and most recreational travelers travel semi-frequently, so there is a stronger case for designing service for workers around the stated preferences of frequent work travelers than there is for designing service for recreational travelers around the preferences of frequent recreational travelers.

*NOTE: Statistical significance was tested using Chi-square tests at the 5% level of significance. 

Optimal Boarding Times

Respondents who travel more frequently are more likely to need service in the middle of the overnight period.

Respondents were asked: “If a safe and affordable night bus service were available between 1AM and 5AM, what is the optimal time you would like to board it?” A cursory look at the distribution of respondents’ self-reported optimal boarding times suggests that potential passengers generally want to board during the earlier portion of the overnight period, but that there is a noticeable uptick right before 5AM. 67% of people who currently travel at night state that they would want to board between 1AM-2:30AM and 83% would board by 3AM. Additionally, there are more travelers who would want to board in the half hour between 4:30-5:00AM than in the preceding hour. This seems to imply that merely extending service until 2:30AM and restarting it at 4:30AM would meet the needs of the majority of overnight travelers. 

Digging deeper, however, individuals who travel overnight more frequently (who are more likely to use overnight buses) are less likely to be satisfied by a proposal that merely extends service by a couple of hours or that operates at the shoulders of the 1 AM – 5AM service period. For frequent travelers, a considerable 31% of worker travelers leaving work and 26% of worker travelers leaving non-work locations would board between 2:30AM and 4AM. For semi-frequent work travelers, this drops to 19% of those leaving work and 16% of those leaving non-work locations. For infrequent work travelers, only 15% of those leaving work and 8% of those leaving non-work locations would board between 2:30 AM and 4 AM.

Recreational travelers also exhibit this positive correlation between travel frequency and a preference for boarding in the middle of the night. While recreational travelers almost exclusively travel late at night (as opposed to early in the morning), respondents who travel less frequently are more likely to want to board earlier in the late night period. 40% of frequent recreational travelers, but only 20% of semi-frequent recreational travelers, and 11% of infrequent recreational travelers would board after 2:30AM. 

For both work travelers and recreational travelers, a service that merely extends the current service period by an hour or two would satisfy fewer of the most frequent travelers. Especially given that these potential passengers are also the most likely to use this service, their unique preferences with regards to boarding times shouldn’t be ignored.