Geographically Weighted Quantile Regression (GWQR): An Application to U.S. Mortality Data

In recent years, techniques have been developed to explore spatial nonstationarity and to model the entire distribution of a regressand. The former is mainly addressed by geographically weighted regression (GWR), and the latter by quantile regression (QR). However, little attention has been paid to combining these analytical techniques. The goal of this article is to fill this gap by introducing geographically weighted quantile regression (GWQR). This study briefly reviews GWR and QR, respectively, and then outlines their synergy and a new approach, GWQR. The estimations of GWQR parameters and their standard errors, the cross‐validation bandwidth selection criterion, and the nonstationarity test are discussed. We apply GWQR to U.S. county data as an example, with mortality as the dependent variable and five social determinants as explanatory covariates. Maps summarize analytic results at the 5, 25, 50, 75, and 95 percentiles. We found that the associations between mortality and determinants vary not only spatially, but also simultaneously across the distribution of mortality. These new findings provide insights into the mortality literature, and are relevant to public policy and health promotion. Our GWQR approach bridges two important statistical approaches, and facilitates spatial quantile‐based statistical analyses. En los últimos años se han desarrollado diversas técnicas para explorar tanto la heterocedasticidad (o no estacionariedad) espacial, así como para modelar toda la distribución de una variable dependiente. El primer tema ha sido abordado principalmente por la regresión ponderada geográficamente (Geographically Weighted Regression ‐GWR), y el segundo por la regresión por cuantiles (Quantile Regression‐QR). La combinación de ambas técnicas analíticas, sin embargo, ha recibido mucho menos atención. El objetivo de este artículo es llenar dicho vacío mediante la propuesta de una regresión geográficamente ponderada por cuantiles (Geographically Weighted Quantile Regression‐ GWQR). Los autores resumen brevemente las técnicas GWR y QR respectivamente, y luego esbozan sus propiedades sinérgicas. Luego presentan la nueva técnica propuesta: GWQR. Los autores abordan los temas de las estimaciones de los parámetros GWQR y sus errores estándar, el criterio de selección del ancho de banda de la validación cruzada (cross‐validation bandwidth), y la prueba heterocedasticidad espacial. Como ejemplo se aplica GWQR a datos de la tasa de mortalidad como variable dependiente y cinco determinantes sociales como variables independientes para los condados de los Estados Unidos. Los patrones espaciales se presentan en mapas con los resultados del análisis para los percentiles 5, 25, 50, 75, y 95. Los resultados muestran que las asociaciones entre la mortalidad y sus factores determinantes no sólo varían espacialmente, sino también de forma simultánea a través de la distribución de la tasa de mortalidad. Estos nuevos hallazgos coinciden con la literatura de los estudios de mortalidad, y son relevantes para aplicaciones de política pública y promoción de la salud. El enfoque GWQR representa un puente conceptual y metodológico entre dos enfoques estadísticos importantes a la vez que hace más factible el análisis estadístico espacial por cuantiles. 近年来,可用于探讨空间非平稳性和模拟回归变数分布的技术得到发展。前者主要用地理加权回归方法（GWR）处理,后者采用分位数回归（QR）处理。然而对这些分析技术的结合使用却很少关注。本文试图通过提出地理加权分位数回归（GWQR）来填补这一空白。在分别简要回顾了GWR和QR方法的基础上,基于两个方法的协同应用提出了GWQR新方法,进而讨论了GWQR的参数估计、标准误差、带宽选择标准的交叉验证和非平稳性检验。本文将死亡率作为因变量及五个社会因子作为解释变量,进行了美国县域单元的案例研究,绘制了0.05、0.25、0.5、0.75和0.95不同百分位点的分析结果图。研究发现,死亡人数不仅与解释变量的空间分布相关,同时也与其地理分布相关。这些新发现不仅可促进对死亡率相关成果的深入分析,同时也与公共政策和健康促进有关。GWQR方法架构了QR和GWR两种重要统计方法之间的纽带,也促进了基于分位数的空间统计分析方法的发展。     

Homeland Heroes: Migrants and Soldiers in the Neoliberal Era

This paper examines the dynamic relationship between neoliberalism and nationalism through the counterintuitive comparison of journeys travelled by US citizens as they enlist in the military and by unauthorized Central Americans as they migrate to the United States. We argue that, however different the context and content of their decisions and their lives, Central American migrants and US soldiers are both connected within a larger political economy. We complicate the idea of migrants and soldiers as purely rational economic actors, but we also reject the idea, imputed onto migrants and soldiers by neoliberal states, that they are naturally nationalistic actors. Migrants and soldiers embody a neoliberal subjectivity produced through processes of violence, capital accumulation and militarization. Yet, as we examine throughout this paper, their construction as homeland heroes within the national imaginary masks the ways their labor and their mobility serve the institutionalization of neoliberal statecraft.     

Land-beach-risk-scape: deciphering the motivators of risk-taking at the beach in Australia

Abstract

This article considers risk-taking associated with the popular leisure activity of beach going in Australia. It investigates the risk-taking proclivities and cultural protocols in Australian beach use which, to date, have received little research attention. Drawing on the testimonies of beachgoers, we provide a discussion on how risk can be both voluntary as well as accidental at the Australian beach. While accidental risk-taking can be attributed to a lack of beachscape safety or lack of hazard knowledge, it is often the result of peer, sociocultural and psychodynamic influences that result in the production and reproduction of a pervasive culture of risk-taking. This culture is explored via the influence of the enculturation of risk into Australian beach practices, the attenuation of safety perceptions among beachgoers, and the attraction to risky behaviours that affect those in the beach space. The reproduction of risk in Australian beach use and the feeling of attachment observed among research participants have been conceptualised as the embodied societal subject, as identified through geographic psychoanalysis. A psychoanalytic geographic interpretation of participant attitudes and beliefs concerning risk-taking and beach use has been used to theorise how the prevailing discourses and fantasies of Australian beach use shape this site-specific culture of risk.     

Form and deformity: the trouble with Victorian pockets

This essay explores the Victorian debate about the place of pockets in men's and women's clothing. By studying the representation of men as naturally pocketed creatures and the general denial of useful pockets to middle-class women, the essay demonstrates the tenacious cultural logic by which men's and women's pockets were imagined to correspond to sexual differences and to index access, or lack thereof, to public mobility and financial agency. Interconnected readings of visual art, essays, and novels show how the common sense about gendered pockets was utilized and promulgated in Victorian narratives. The question of who gets pockets is thus positioned as part of the history of gendered bodies in public space.     

Collaborating With Sex Workers in Oral History

It took several decades for sex workers to become true speakers,rather than testifiers to the speech of others. Tensions understandablyremain about sharing authority with oral historians. This articlereflects on attempts to share authority in setting up, funding,organizing, and publishing from a UK sex work project. It questionswhether commitment to share authority compromises scholarshipand theoretical development, and how an oral historian's roleis affected by a parallel advocacy role. It explores the formationand boundaries of collaborative relationships and briefly raisesthe issue of crossing legal boundaries in less orthodox projectwork and implications for ethical permissions.     

Sale, price and valuation in Galicia and Castile–León in the tenth century

The number of sale transactions recorded by northern Spanish charters of the tenth century is very striking, especially in the 930s to 960s. A record of price paid was a consistent element of such documents, although words used to express price varied from silver solidi to goats, shirts and grain. Valuations, in solidi and in other units of account such as cattle, were often stated when objects were used as payment. While it looks as if some silver was really used in deals in urban León and its hinterland, using pieces of silver called argenzos , argenteos etc., elsewhere this was rare. Comparing the transactions in the three very different monastic collections of Celanova in the north–west, Sahagún in the central meseta and Cardeña in the foothills of the sierras in the north–east, regional difference is also striking. Sahagún is notable for the volume and early date of its sales and for increasing use of silver–based expressions of price and value. Round Celanova, by contrast, although there were also many sales, people used several modes of valuation simultaneously, but metal–based notions very rarely. Round Cardeña, close to urban Burgos, far fewer sales are recorded, and they come later in the century, but silver–based notions of value were the only ones used. This latter sub–urban context seems to have been much less commercially active than that of León and Sahagún, with exchange by gift and countergift a more prominent characteristic.