A quasi-experimental study of light rail transit on jobs-housing balance by regional typology: A case study of South Korea

Light Rail Transit (LRT) systems have been introduced across various regions of South Korea to address travel needs and promote sustainable urban development. Jobs-housing balance was one of the top priorities for city management in these schemes. However, a lack of an integrated plan for LRT and jobs-housing opportunities has resulted in excess commuting, which contradicts the expected outcome of providing an LRT system. Existing literature has reported mixed findings on jobs-housing balance. These seemingly perplexing results would arise from methodological limitations that fail to adequately control for confounding variables and explain variations among regional types. The study analyzes changes in jobs-housing balance after the intervention of LRT systems in different urban contexts. This study categorizes regional typologies of LRT service areas into three types—type1 if a line connects “periphery-metropolitan center-periphery” areas; type2 if a line connects “city center-periphery”; type3 if a line serves “metropolitan center.” The study employs a quasi-experimental design incorporating propensity score matching (PSM) and difference-in-difference regression. PSM matches treatment and control groups that have similar characteristics. Subsequently, difference-in-difference regression modeling estimates the treatment effects on jobs-housing balance resulting from LRT system operations. The PSM results confirm the varied impacts of LRT operations on the jobs-housing balance depending on the different regional types. Types 1 and 2, linking the metropolitan or surrounding city centers with the urban peripheries, experience significant imbalances, while the control groups show greater jobs-housing balance after the introduction of LRT. However, type 3 serving metropolitan centers demonstrates no significant difference between treatment and control groups. The DID results indicate that the treatment effect is only significant in type 1. In conclusion, LRT systems, which mainly connect urban peripheries and centers, are more likely to cause a mismatch between jobs and housing distribution. The results suggest an integrated approach between LRT and the built environment, such as transit-oriented development (TOD), that promotes a jobs-housing balance by locating jobs and affordable housing near LRT stations.