2021

Farrukh Baig, Dalian University of Technology
Farrukh Baig, Dalian University of Technology
Dong Zhang (zhangdong@dlut.edu.cn), Dalian University of Technology
Jaeyoung Lee, Central South University
Hongda Xu, Dalian University of Technology

The continuous increase in the elderly population and the need for disability-inclusive public transportation propelled agencies to implement policies to ensure seat availability for vulnerable users.  Although most of the public transportation provides a few priority seats for vulnerable users, the issue of seat availability remains there due to its small quantity and its usage by regular passengers. To extend the theory of planned behavior (TPB), this study aims to evaluate how empathic concerns, attitude, injunctive norms, descriptive norms, and perceived behavioral control contribute to the behavioral intentions and actual conducts of yielding seats to vulnerable passengers with a university students’ survey responses in China. A partial least square path modeling based structural equation modeling (SEM) approach was employed to test the postulated hypotheses. Findings revealed that empathic concerns significantly promote the yielding seat intention and, thus, the actual conduct through its impacts on attitude, injunctive norms, and perceived behavioral control. The implications of “soft measures” to support the transportation policy for a sustainable and disability-inclusive public transportation service are discussed accordingly.

Eric Morris (emorri7@clemson.edu), Clemson University
Kelcie Ralph, Rutgers University
Jaekyeong Kwon, Rutgers University

People with disabilities tend to participate in fewer out-of-home activities, raising concerns about their well-being. This paper investigates travel and activity barriers faced by people with disabilities using data from the American Time Use Survey in the years 2008-2018. After establishing that out-of-home activities are important for subjective well-being, we focus on realized access, which we measure using “travel time prices,” i.e., the number of travel minutes associated with each minute of out-of-home activity time. We presume that less travel and more activity participation, and thus a lower travel time price, are desirable. We find that, in the aggregate, working-age people with disabilities pay a travel time price about 11.2 percent higher when controlling for demographics. The most problematic travel/activity couplets are work (10.9 percent higher), volunteering (30 percent higher), and shopping/services (7.7 percent higher). Physical disability (difficulty walking or climbing stairs) is associated with the greatest disadvantage (a travel time price 18.6 percent higher). Our evidence suggests that the premium is driven primarily by differences in activity participation (predicted to be 3 minutes shorter per activity for those with disabilities), not longer trips. The latter result suggests that for many people with disabilities who do travel, travel itself might not be the main barrier, at least to the extent that travel time serves as a proxy for the generalized costs of travel. However, these results only apply to those who participated in activities outside the home, not the 33.4 percent of people with disabilities who did not.

Ming Lee, Florida International University
Xia Jin, Florida International University
Fahmid Tousif, Florida International University

A comprehensive examination of the 2017 National Household Travel Survey (NHTS) data was conducted to identify the mobility needs and challenges faced by older adults (i.e., age 65 and older) in urban, suburban, and rural environments. Data pertaining to older adults in the NHTS dataset were divided into three age groups: age 65 to 74, 75 to 85, and 85 and older. Travel behavioral variables examined include average daily trip rate, average daily person miles traveled, trip purposes, and trip modes. Personal characteristics relevant to potential mobility challenges include age, gender, residential environment, income level, and ambulation assistive devices required for daily activities. Cross tabulation of these variables was used to elicit consistent patterns of inter-relationships among the variables to see how age and environment can affect mobility of older adults. Findings from the analysis confirm common conjectures that average number of daily person trips and daily person miles generally decreased with increasing age as well as decreasing urbanization of the environment. This general pattern also applied to those requiring ambulation assistance to a certain degree. Daily person trip rates also increased consistently as income levels increased, while older females tend to travel less frequent and shorter distance than their male counterparts. Privately owned vehicles (POVs) were the dominant transportation mode in the U.S with a significant lack of alternatives in the suburban and rural areas. We identified with evidence from the data that older adults in urban areas with low income are most vulnerable for adverse consequences of immobility.

Abigail Cochran (acochran@unc.edu), University of North Carolina, Chapel Hill

People with disabilities may be particularly vulnerable to the direct health effects of the COVID-19 pandemic, as well as the wider impacts of the pandemic response. People with disabilities experience numerous barriers to using transportation and accessing essential goods, like fresh food, and services, like medical care, that are necessary for maintaining health. The pandemic and the pandemic response threaten to exacerbate persistent health disparities between people with and without disabilities. To avoid this, it is important that those involved in the pandemic response understand and address problems that excessively burden people with disabilities. To better understand difficulties that individuals with disabilities are facing using transportation and meeting their needs during the pandemic, I conducted in-depth interviews with 21 San Francisco Bay Area residents with disabilities between March 20 and April 6, 2020, immediately following adoption of the first shelter-in-place orders in the region. Analyzing these interviews, I find that the pandemic is underscoring many difficulties accessing transportation and other essentials that people with disabilities regularly encounter. These include challenges accessing reliable and safe transportation as well as up-to-date communications about transportation and public health, and difficulties getting needed assistance using transportation and completing activities of daily living ranging from personal care to getting groceries. I recommend that those involved in the pandemic response make a concerted and intentional effort to address barriers to accessing needed transportation, communications, and assistance that people with disabilities are facing during the pandemic, paving the way for a more inclusive pandemic response.

Dahai Han, University of Wisconsin, Milwaukee
Yura Lee (lee626@uwm.edu), University of Wisconsin, Milwaukee
Jie Yu, University of Wisconsin, Milwaukee
Corie Dejno, Interfaith Caregivers of Washington County

This study examined differences in older adults’ travel patterns between drivers and non-drivers in suburban and rural areas, using data collected from 502 respondents aged 65 and older from a survey in Washington County, Wisconsin. Binary and ordered logistic regression models were conducted to determine whether older adults’ driving status was significantly associated with their trip purposes and trip frequency by mode, while controlling for covariates including socio-demographic characteristics. Results from logistic regression analyses showed that: 1) Non-driving older adults were more likely to make maintenance trips (e.g., medical or dental appointments, food pantry) but less likely to make leisure trips (e.g., socializing, movies/art/theater) than driving counterparts. However, there were no significant difference in subsistence trips (e.g., worship, work) between drivers and non-drivers; 2) While making more trips via dependent modes (e.g., riding with family or friends, public transit), non-driving older adults traveled less frequently than older drivers overall, because they made much fewer trips via independent modes (e.g. driving, walking). After identifying the mobility needs and limitation for older adults who do not drive by comparing all-mode transportation patterns between driving older adults and non-driving ones, this study further explored several transportation barriers encountered by non-driving older adults. Findings suggest that improvement of alternative transportation services (e.g., advanced vehicle scheduling methods, inter-county transit service collaboration), usage of assistive technology, and education of transportation service awareness will be needed to help improve mobility among non-driving older adults in suburban and rural areas.

Mingqi Yao, University of California, Irvine
Suman Mitra, University of Arkansas, Fayetteville
Stephen Ritchie, University of California, Irvine

This paper analyzed travel diary data from the 2017 National Household Travel Survey to examine the heterogeneities in travel time and activity durations of US older adults (aged 65+). To identify the heterogeneities resulting from activity sequences, older adults were partitioned into eight and seven clusters based on their weekdays and weekend activities, respectively. The study then estimated a hazard-based duration model with random effects for each distinct cluster to account for individual-level unobserved heterogeneities. Results of the model estimation showed that the hazard relationships between different types of activity-travel times and activity durations varied across clusters. The individual-level unobserved heterogeneities imposed substantially greater influence to travel times than activity durations of older population. Our results also found that female older adults, on average, traveled a shorter time while spent more time in activity participation than their male counterparts. Generally, older adults inclined to spend more time in activity engagement if their travel time were longer. The expectancy of travel times for urban older adults was significantly less than their rural counterparts; however, this urban/rural location did not have any substantial influence in activity durations. Transferability test results suggested that older adults’ trip and activity durations on weekdays and weekends should be modeled separately regardless of similar activity sequences. This study will help transportation planners and policymakers understand the differences in travel time and activity duration of elderly mobility, thereby facilitating the development of policies targeting the special needs of different elderly groups to improve their transportation options.

Sunghoon Jang (s.jang@tue.nl), Eindhoven University
Yongju Yi, Ajou University
Jeong Ah Jang, Ajou University
Keechoo Choi, Ministry of Land, Infrastructure, and Transport

This study explores stated preference of the physically disabled people for wheelchair-accessible express bus in the context of mode choice in the inter-city travel. In particular, the study focuses on heterogeneity in the adoption behavior by socio-demographics, disability grade, and their intention to increase number of inter-city travel. A latent class mixed logit incorporating panel effect was applied to explore inter- and intra-personal heterogeneity. A face-to-face stated choice experiment for the physically disabled people is used to estimate the model. Results indicates that both inter- and intra-personal heterogeneity shows statistically significant. The inter-personal heterogeneity was discontinously seperated to the classes by some socio-demographics, disability grade, and their intention to increase number of inter-city travel, affecting their value of time, then the continuously distribtued personal heterogeneity is significantly observed in all the classes. We further show that the adoption probability is higher in the group with lower value of time. On average, the adoption probabilities are more senstive to increase travel time or decrase travel cost of the wheelchair-accessible express bus.

Ryan Best, RAND Corp
Laura Fraade-Blanar, RAND Corp
Marjory Blumenthal, RAND Corp

The introduction of automated vehicle (AV) technologies to the roadways has the potential to improve road safety and reduce traffic crashes and associated adverse outcomes. As a cutting-edge technology where few have personal experience, individuals’ initial perceptions of the safety of AVs will likely stem from communications originating from a number of industry stakeholders, including AV companies themselves, outside regulators, and governing bodies. There will likely be differences in the relative influence of these messages depending on the source and content of information. Considering that aging is commonly associated with a reduction of driving, older adults may prove to be a population on the forefront of AV adoption and it is especially important to understand what factors influence their perceptions of AVs. A survey instrument was developed to both implicitly and explicitly estimate how personal perceptions of AV safety are influenced by safety messages from different sources. Analysis of the implicit measure revealed that decreasing age was generally associated with higher perceptions of AV safety. Compared to adults of higher ages, younger adults were particularly influenced by positive safety-related information provided by average AV crash rates and official statements from AV companies. When measured explicitly, increased age was associated with a larger preference for safety-related messages from safety advocacy groups and a decreased preference for information from average crash rates and AV companies. Results are discussed in terms of how safety related messages from various stakeholders might be utilized to affect perceptions of AVs across adulthood.

Aditi Misra, University of Michigan
Manish Shirgaokar (manish.shirgaokar@ucdenver.edu), University of Colorado, Denver
Asha Agrawal, San Jose State University
Bonnie Dobbs, University of Alberta
Martin Wachs, University of California, Los Angeles

Ride-hailing services like Lyft and Uber have the potential to improve mobility for many older adults, especially those who cannot or prefer not to drive. However, ride-hailing services have to date mostly required booking via apps or online. Some advocates for older adults’ mobility are concerned that many seniors will be unable or unwilling to use online technologies. We used survey data from 2,917 Californians 55 years and older to investigate how older adults who currently ride-hail booked their trips, and if their attitudes towards technology were correlated with booking trips online versus by phone or with help. We specified four binary probit models in which the outcome variables are the manner in which a respondent accessed ride-hailing services: self-booked by phone, self-booked by app, booked by a family/friend/caregiver but rode alone, or booked by others and rode with them. We controlled for two attitudinal constructs, residential location, general travel behavior, physical health, and standard socio-economic factors. We found that respondents who were more confident towards technology booked via apps, while those who were more cautious about technology depended on phone booking, or relied on others, and were less likely to book using apps. Particularly, those who were suburbanites, non-reliant on others for rides, had physical health issues, were college educated, or non-Hispanic tended to book via apps. Our findings provide a basis to think about expanding ride-hailing to other older adults, particularly those who are not comfortable with technology, through convenient access to ride-hailing booking.

Hany Hassan, Louisiana State University
Matthew Lauzon, Queen's University
Mark Ferguson, McMaster University
Bruce Newbold, McMaster University
Brenda Vrkljan, McMaster University
Saiedeh Razavi, McMaster University

keeping a balance between maintaining older peoples’ mobility with their own and other road users’ safety has been always a challenge. Therefore, it is important to understand everyday mobility issues that elderly people are facing as well as challenges/factors associated with driving cessation. This paper aims to identify and quantify contributing factors that affect older adults’ satisfaction with their everyday mobility using ordered probit (OP) modeling. Underlying this objective is to provide better understanding regarding factors that may influence older adults to stop driving. The data used in the analysis was obtained through an online survey that was conducted with 1000 Canadians aged 65+. The results of the OP model indicated that several factors affect older adults’ satisfaction with their everyday mobility including driving a car to reach destinations, ability to drive a car alone (without the need for help from others), experiencing difficulties / challenges associated with driving, having a physical health issue that restricts an older adult’s ability to walk, fear of falling while walking and inability to visit local places that older adults wish they could visit more often. The findings also suggested that factors influencing older drivers’ decision to retire from driving (for those who have already retired driving) are in fact different from the perceived factors for those who are still driving. The results of this study provide insights about policies and countermeasures that can be implemented to improve the safety and mobility of the aging population.

Madeline Ruvolo, University of California, Los Angeles

Thirty years after the passage of the Americans with Disabilities Act, people with disabilities still face significant barriers to transportation access. In recent years, new transportation services known as “new mobility” or “emerging mobility” launched entirely without accessible options. These services include transportation network companies (TNCs) such as Lyft and Uber, bike share, scooter share, and car share. Whether cities rush to welcome or grudgingly accept new mobility services, disability access is still too often an afterthought. This paper examines perceptions of new mobility services among disabled people in San Francisco via a survey of 218 people with disabilities. The study finds that disabled people in San Francisco see promise in some new mobility services but currently face significant barriers to use. Out of all new mobility options, respondents were most interested in on-demand automobile access, e.g. accessible TNCs or accessible taxis. Respondents expressed significant concern about scooters and dockless bike share blocking the path of travel, and nearly 75 percent reported that an improperly parked scooter or bike created a mobility barrier for them on at least one occasion. Additionally, with broken sidewalks and missing curb ramps common, people with disabilities still face many barriers to basic mobility. This paper offers the following recommendations: continue advocating for more effective TNC wheelchair accessible vehicle (WAV) regulations at the state level, address the problem of scooters and bicycles on sidewalks, and build safer active transportation infrastructure to decrease conflicts between modes and make public space safer for vulnerable pedestrians.