@article{liu_bardaka_2023, title={Transit-induced commercial gentrification: Causal inference through a difference-in-differences analysis of business microdata}, volume={175}, ISSN={["1879-2375"]}, DOI={10.1016/j.tra.2023.103758}, abstractNote={A plethora of studies has explored the relationship between transit investments and property prices, but very little is known about how new transit projects and transit-oriented development affect nearby businesses and whether they contribute to commercial gentrification. This research presents a quasi-experimental econometric framework for studying transit-induced commercial gentrification from project announcement to post operation using business microdata. Previous urban economics and planning research informs the identification of retail and service business categories associated with the phenomenon of commercial gentrification, including local businesses, chain stores, and businesses offering non-essential or upscale products. Negative binomial models with a difference-in-differences specification enable the temporal and spatiotemporal analysis of business entries, exits, and turnover and the estimation of transit-induced impacts. The developed methodology is demonstrated through an empirical example: the study of the effects of the LYNX Blue light rail line in Charlotte, NC, over a 20-year period. Our study makes a significant contribution to the limited quantitative research on transit and commercial gentrification and is the first to focus on the causal relationship between the two. The application of the analysis framework to other metropolitan areas with transit systems in the future will inform transportation and urban planners on the type of businesses that could be primarily affected and the timing and extent of these effects, and help them design effective and targeted business assistance programs.}, journal={TRANSPORTATION RESEARCH PART A-POLICY AND PRACTICE}, author={Liu, Chang and Bardaka, Eleni}, year={2023}, month={Sep} }
 @article{liu_bardaka_paschalidis_2022, title={Sustainable transport choices in public transit access: Travel behavior differences between university students and other young adults}, volume={5}, ISSN={["1556-8334"]}, DOI={10.1080/15568318.2022.2084656}, abstractNote={Abstract This research investigates the socioeconomic and travel characteristics of student transit users in comparison to other young adults and quantifies behavioral differences in public transit access between these two population groups. Using data from a 2015 system-wide on-board survey in the Denver-Aurora region, CO, we seek to understand whether college and university students make more environmentally sustainable choices when accessing bus and light rail transit as well as identify the determinants of their choices. Our results indicate that student transit riders live in larger households with more vehicles per household member and are located substantially farther from the city center and the light rail compared to other young adults. The majority of student light rail users drive alone to light rail stations and typically do not park at the station that is the closest to their home. On the other hand, most other young adults walk to light rail stations. We also find that travel time and vehicle ownership per household member have a significantly lower impact on student choices. The identified travel differences and behavioral variations between the two population groups may be associated with the lack of affordable housing for students in the central and transit-rich neighborhoods of large metropolitan areas.}, journal={INTERNATIONAL JOURNAL OF SUSTAINABLE TRANSPORTATION}, author={Liu, Chang and Bardaka, Eleni and Paschalidis, Evangelos}, year={2022}, month={May} }
 @article{wan_luo_liu_chang_yamashita_jiang_2021, title={Alternating current poling on sliver-mode rhombohedral Pb(Mg1/3Nb2/3)O-3-PbTiO3 single crystals}, volume={208}, ISSN={["1873-2453"]}, DOI={10.1016/j.actamat.2021.116759}, abstractNote={Sliver-mode 0.73Pb(Mg1/3Nb2/3)O3-0.27PbTiO3 single crystals were poled by the alternating current electric field (ACP) along the [001] direction for low-frequency transducer applications. Under ACP with optimized conditions (2.89 kVrms, 0.1 Hz, 10 cycles), the free dielectric constant (εT33/ε0) was enhanced from 5300 to 7220 and piezoelectric coefficient (d33) was improved from 1410 to 1920 pC/N, both are about 36% higher than those under traditional direct current poling. The piezoresponse force microscopy observation and phase-field simulation show the similar domain morphologies evolution. During the ACP process, the domain morphology first changes from ‘4R’ to ‘2R’ configuration, and then the length of the 109° domain wall keeps increasing, which leads to a longer range of ordering and a stable lamellar domain structure in the end. The correlation between the domain morphology and the coercive field is also found in both the experiment and simulation. These findings on the effect and mechanism of ACP will help develop advanced low-frequency single crystal transducer arrays.}, journal={ACTA MATERIALIA}, author={Wan, Haotian and Luo, Chengtao and Liu, Chang and Chang, Wei-Yi and Yamashita, Yohachi and Jiang, Xiaoning}, year={2021}, month={Apr} }
 @article{guo_li_anastasopoulos_peeta_lu_2021, title={China's millennial car travelers' mode shift responses under congestion pricing and reward policies: A case study in Beijing}, volume={23}, ISSN={["2214-3688"]}, DOI={10.1016/j.tbs.2020.11.004}, abstractNote={This paper investigates the potential impacts of congestion pricing and reward policies on migrant and resident millennial car travelers’ morning commute mode shift responses in China. A stated-preference survey developed for this study was conducted in 2017 among millennial car travelers living or working in Beijing’s inner district, from which approximately 2000 responses were collected. Separate random parameters bivariate ordered probit models were estimated for migrant and resident millennial car travelers to capture the differences between their mode shift responses, unobserved heterogeneity, and correlation between their mode shift responses to congestion pricing and reward policies. Sociodemographic characteristics, travel behavior and needs, residential location accessibility to and by transit, attitudes towards travel and congestion pricing and reward policies were found to affect millennial car travelers’ mode shift responses. In addition, the impacts of the contributing factors on the mode shift responses were very different between the congestion pricing and reward policies and between the migrant and resident millennial car travelers. The findings from the model estimation and descriptive statistics suggest that the implementation of pricing and reward policies, along with other unique regional (e.g., rapid increase in residential property price) and institutional (e.g., household registration system) characteristics, may potentially bring new challenges to migrant car travelers that may add to their economic burden and reduce their quality of life, particularly under congestion pricing policies. This study also provided insights for the design of future congestion pricing and reward policies and complementary measures that could address the travel needs of all travelers.}, journal={TRAVEL BEHAVIOUR AND SOCIETY}, author={Guo, Yuntao and Li, Yaping and Anastasopoulos, Panagiotis Ch and Peeta, Srinivas and Lu, Jian}, year={2021}, month={Apr}, pages={86–99} }
 @article{liu_bardaka_2021, title={The suburbanization of poverty and changes in access to public transportation in the Triangle Region, NC}, volume={90}, ISSN={["1873-1236"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85098110629&partnerID=MN8TOARS}, DOI={10.1016/j.jtrangeo.2020.102930}, abstractNote={During the last 50 years, a number of economic forces led to noteworthy changes in the geography of poverty in the US. Employment decentralization and lack of affordable housing have resulted in many low-income households migrating to suburban areas, and as of today, the majority of the low-income population of metropolitan regions resides in the suburbs. Focusing on the Triangle Region, NC, this study systematically explores the changes in the geography of poverty and transit access over time to better understand how accessibility to transit has changed for the low-income residents. Spatial panel data models are also estimated to investigate the relationship between poverty and transit access at the neighborhood level and how it varies spatially and temporally, while accounting for unobserved heterogeneity and spatial autocorrelation. Results indicate that between 1990 and 2015, the outer-ring suburbs experienced the highest increase in both poverty and transit access, although improvements in transit access were lower in the recently urbanized areas within the outer-ring suburbs. Inner-ring suburbs experienced a substantial rise in poverty rate and low-income population, and a comparable increase in transit access. Central cities remained the areas with the highest poverty rate and transit access in the Triangle Region but experienced smaller changes over time compared to suburban areas. The findings of the econometric analysis suggest that poverty rate and transit access are not significantly related at the neighborhood level when time-invariant unobservable characteristics are accounted for.}, journal={JOURNAL OF TRANSPORT GEOGRAPHY}, author={Liu, Chang and Bardaka, Eleni}, year={2021}, month={Jan} }