Comparison between OLS and GAM.

The deployment of public electric vehicle charging stations (EVCS) is a critical component of transportation electrification. Recent studies have highlighted growing concerns about disparities in accessibility to public chargers between different demographic groups. This research expands ongoing equity concerns by contextualizing existing transportation equity discourse and analyzing public charger access disparities in Austin, Texas. Using threshold equity toolkits, we investigated public EVCS access disparity across different races and income groups. We conducted a generalized additive model regression to measure and visualize the effects of possible determinants on public EVCS access. The analysis results revealed that a public EVCS access disparity exists in Austin, with most chargers being installed in areas where the majority of the population is Non-Hispanic White. There was a more equal distribution of public EVCSs across income quartiles when compared with race. However, middle- and high-income groups had better access than lower-income communities in terms of distance to the nearest public EVCSs. Our regression analysis found that regional and socio-demographic factors, such as race and income, have a statistically significant impact on public charger access. The regression analysis also revealed that Austin’s current public EVCS deployment seems to favor communities above the poverty level and with higher numbers of registered electric vehicles. Local policymakers should reflect on the findings of this study to develop an equitable transportation electrification plan. Federal environmental justice plans such as the Justice40 initiative can benefit from incorporating more local contexts to better invest in disadvantaged communities.公共电动汽车充电站（Electric Vehicle Charging Stations, EVCS）的部署是交通电气化的关键组成部分。近期研究已凸显出，不同人口群体间公共充电桩可达性差异引发的担忧日益加剧。本研究通过锚定既有交通公平话语的具体语境，分析美国得克萨斯州奥斯汀市的公共充电桩可达性差异，进一步拓展了当前关于公平性的研究议题。本研究采用阈值公平工具箱（threshold equity toolkits），探究了不同种族与收入群体间的公共EVCS可达性差异。我们通过广义加性模型回归（generalized additive model regression），对影响公共EVCS可达性的潜在决定因素进行量化与可视化分析。分析结果显示，奥斯汀市存在公共EVCS可达性差异：绝大多数充电桩布局在人口以非西班牙裔白人为主的区域。相较于种族维度，公共EVCS在不同收入四分位群体间的分布更为均衡。但就前往最近公共EVCS的距离而言，中高收入群体的可达性优于低收入社区。回归分析结果表明，种族与收入等区域及社会人口学因素对公共充电桩可达性具有统计学意义上的显著影响。此外，回归分析还显示，奥斯汀市当前的公共EVCS部署似乎更倾向于贫困线以上以及注册电动汽车数量较多的社区。地方政策制定者应参考本研究结论，制定公平的交通电气化发展规划。诸如Justice40倡议等联邦环境公平计划，可通过融入更多本地语境，优化对弱势社区的投资，从而获得更好的实施效果。