Rebates incentivize clean vehicle adoption but may raise equity concerns because upfront capital is required for vehicle acquisition, limiting access for low-income households. Since poorer communities typically experience worse air quality than their wealthier counterparts, rebates also may not incentivize clean vehicle acquisitions in more polluted areas where air quality benefits would be greater. We analyzed whether equity-promoting policy design elements changed the associations between rebate allocation rates and census tract characteristics including community disadvantage, household income, education, race and ethnicity, and ambient air pollution in two California rebate programs. We found that the Clean Vehicle Rebate Project issued more rebates per household to advantaged, higher-income, better-educated communities with more White residents and intermediate levels of ambient nitrogen dioxide (NO2). An income cap and income-tiered rebate amount introduced part way through the program improved distributional equity, but fewer rebates were still issued to lower income, less-educated census tracts with higher percentages of Hispanic and non-Hispanic Black residents. Furthermore, these policy design elements reduced the overall number of rebates that were distributed. In the Enhanced Fleet Modernization Program, which incorporates additional equity-related design elements, rebate allocation rates were positively associated with community disadvantage, lower income and education, and a higher proportion of Hispanics, and were the highest in areas with slightly higher NO2 levels. These findings indicate that design elements such as an income cap, income-tiered rebate amounts, expanded vehicle eligibility, and increased benefit eligibility in disadvantaged communities, can facilitate distribution of rebates to more socioeconomically diverse populations with higher air pollution burdens.

中文翻译：

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加州清洁车辆回扣计划的公平性分析

回扣鼓励采用清洁汽车，但可能会引起公平问题，因为购车需要前期资金，限制了低收入家庭的使用。由于较贫穷的社区通常比富裕的社区经历更糟糕的空气质量，因此在空气质量效益更大的污染严重地区，回扣也可能不会激励购买清洁汽车。我们分析了促进公平的政策设计元素是否改变了加州两个退税计划中退税分配率与人口普查区特征（包括社区劣势、家庭收入、教育、种族和民族以及环境空气污染）之间的关联。我们发现，清洁汽车返利项目为每户家庭提供更多返利给有优势的、收入较高的、受过良好教育的社区，拥有更多的白人居民和中等水平的环境二氧化氮 (NO2)。在该计划中引入了收入上限和收入分层回扣金额，改善了分配公平，但仍向收入较低、受教育程度较低、西班牙裔和非西班牙裔黑人居民比例较高的人口普查区发放了较少的回扣。此外，这些政策设计元素减少了发放的回扣总数。在包含额外公平相关设计元素的增强型舰队现代化计划中，回扣分配率与社区劣势、较低的收入和教育以及较高的西班牙裔比例呈正相关，并且在 NO2 水平略高的地区最高。