Geographical concentration of COVID-19 cases by social determinants of health in 16 large metropolitan areas in Canada - a cross-sectional study

Background: There is a growing recognition that strategies to reduce SARS-CoV-2 transmission should be responsive to local transmission dynamics. Studies have revealed inequalities along social determinants of health, but little investigation was conducted surrounding geographic concentration within cities. We quantified social determinants of geographic concentration of COVID-19 cases across sixteen census metropolitan areas (CMA) in four Canadian provinces. Methods: We used surveillance data on confirmed COVID-19 cases at the level of dissemination area. Gini (co-Gini) coefficients were calculated by CMA based on the proportion of the population in ranks of diagnosed cases and each social determinant using census data (income, education, visible minority, recent immigration, suitable housing, and essential workers) and the corresponding share of cases. Heterogeneity was visualized using Lorenz (concentration) curves. Results: Geographic concentration was observed in all CMAs (half of the cumulative cases were concentrated among 21-35% of each city's population): with the greatest geographic heterogeneity in Ontario CMAs (Gini coefficients, 0.32-0.47), followed by British Columbia (0.23-0.36), Manitoba (0.32), and Québec (0.28-0.37). Cases were disproportionately concentrated in areas with lower income, education attainment, and suitable housing; and higher proportion of visible minorities, recent immigrants, and essential workers. Although a consistent feature across CMAs was concentration by proportion visible minorities, the magnitude of concentration by social determinants varied across CMAs. Interpretation: The feature of geographical concentration of COVID-19 cases was consistent across CMAs, but the pattern by social determinants varied. Geographically-prioritized allocation of resources and services should be tailored to the local drivers of inequalities in transmission in response to SARS-CoV-2's resurgence.

Emerging diasporas: Exploring mobilization outside the homeland

An enormous number of people are leaving their homelands around the world today. This has happened several times in the past, but migration has spiked in recent years. These population movements can have significant effects on both the host country (where emigrants or refugees settle), as well as politics back in the homeland. After they leave their homelands, why do some groups mobilize, and in what ways? In this article, we examine a number of factors that may impact when emigrated groups mobilize after they move. We develop a new dataset on potential diasporas in the United States to evaluate a series of hypotheses; including those about motivations for mobilization such as identity maintenance, the objective plight of co-ethnics in the homeland, and group capacity to mobilize. We find some merit in the identity preservation argument and a strong effect of geographic concentration of the diaspora segment. Surprisingly, diaspora mobilization does not appear to be strongly related to conflict in the homeland among these groups.

Industrial Energy Regulation: The Role of Business Conglomerates in China

This paper characterizes the importance of ownership networks of firms that are subject to a prominent energy regulation in China: the Top 1000 Enterprises Energy-Saving Program. We use data on the activities of regulated and unregulated firms that are part of the same conglomerate to study the overall importance of conglomerates as well as their geographic concentration. Accounting for business networks of regulated firms significantly increases the fraction of output that is affected by the regulation. We also document that most related firms of Top 1000 firms are located in the same province.

Ethnic Enclaves

Ethnic enclaves have been defined in numerous ways. The word “ethnic” is often used to refer to a particular group with a shared nationality or cultural background. Enclaves sometimes refer to the concentration of ethnic groups within a geographic area. Academic inquiry of ethnic enclaves began with Kenneth Wilson and Alejandro Portes’s study of the “immigrant enclave” formed by Cubans in Miami, which they define as a concentration of ethnic businesses employing people from the same ethnic group. Researchers have tested, expanded, and modified the “enclave hypothesis”—ethnic concentration having a protective effect against a generally hostile climate facing immigrants and ethnic minorities. Depending on the author an enclave may refer to the geographic concentration of migrants and coethnics in a neighborhood; a place with social and economic structures that diverge from those in the surrounding area; or a concentration of economic activity, particularly businesses owned and staffed by members of a single ethnic group. In the strictest sense, ethnic enclaves are made up of a high concentration of an ethnic group within a geographic space, including a large number of business owners from that community. There have been examples throughout US history of ethnic enclaves, including Cubans in Miami, New York’s Chinatown, Japanese and Korean enclaves in California, and Jewish communities in Manhattan. There are also immigrant enclaves across the world. The protective effects of enclaves are largely related to the concentration of economic power to support social, cultural, and political development for immigrant communities committed to sustaining community life within the country where an enclave is formed. Many researchers have used a partial definition of ethnic enclaves only in terms of residential concentration. From this point of view, the existing evidence shows mixed effects for living in an enclave depending on the context, aspects of the enclave studied, and relative outcomes of interest. When applied and compared, the similarities between enclaves and other community formations, such as barrios and ghettos, become relevant. Segregation most frequently serves dominant groups who use isolation to disproportionately apportion resources and exploit marginalized workers. Yet, as Cathy Yang Liu has shown, a concentration of opportunities can lead to strong social and cultural networks within ethnic enclaves. Researchers using the concept of ethnic enclaves can benefit from considering the multilayered factors of immigration, ethnic difference, urban environments, economic systems, health, and power differentials between and among residents in ethnic enclave communities and beyond.

Geographic impressions in Facebook political ads

Online political advertising is becoming increasingly popular as political campaigns recognize the utility of social network platforms, like Facebook, for reaching and engaging with voters. Yet, contrary to the wealth of information about campaign advertising on TV, little is known about advertising online, as comprehensive data only recently became available to scholars. Moreover, the newly available data is often aggregated, incomplete, and imprecise. Here, we present an analysis of Facebook political ad data, supplemented with funding-related meta-data obtained through human coding and a partnership with the Center for Responsive Politics. Through computational tools—namely, network analysis—we aim to use this data to describe and categorize political ad funding behavior on Facebook. Specifically, we focus on the geographic concentration of ads, and discover that most ads reach an audience in a single geographic region (i.e., U.S. state) or in a wide range of regions, and very few reach an audience spanning a small number of regions. We use this observation to partition funding entities into three groups based on their relationships to regionally-concentrated ads. We then examine the differences between these groups via bipartite networks connecting funding entities to their geographic audiences, as well as content they support. Our findings reveal that geographic impressions play an important role in online political advertising, and can be used to classify funding entities. As a result, this study represents a step toward ensuring political funding transparency and demystifying online political advertising more broadly.