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311.
312.
The growth in macro-level income inequality in the United States is well established, but less is known about patterns of inequality at subnational scales and how they vary between and within rural and urban localities. Using data from the Decennial Census and American Community Survey, we produce estimates of within-county income inequality from 1970 to 2016 and analyze differences in inequality levels, the persistence of high (low) inequality, and populations' exposure to high (low) inequality across the rural-urban continuum. We find that income inequality has historically been higher in non-metropolitan than metropolitan counties, but inequality levels converged by 2016 due to growing inequality in metropolitan counties. Additionally, levels of inequality were generally persistent within counties over time, except that counties characterized by low inequality in 1970 were unlikely to remain as such in 2016. Third, non-trivial shares of the metropolitan population resided in low-inequality contexts in 1970, but virtually none of the U.S. population resided in such places by 2016. Residence in high-inequality counties is normative in rural and urban America. This statistical analysis provides an updated portrait of income inequality across the rural-urban continuum, and should spur additional research on stratification in rural America during an era of growing inequality. 相似文献
313.
Urban Ecosystems - Residential yardscapes are at the forefront of human interaction with nature for those living in urban areas across Europe and North America. In recent years a significant amount... 相似文献
314.
Bernard C. Perley 《Journal of Sociolinguistics》2020,24(1):139-143
315.
H. William Amos 《Journal of Sociolinguistics》2020,24(1):55-74
In recent decades, sociolinguists have begun to challenge the traditional view that multilingualism is fundamentally composed of discrete systems known as ‘languages’. Supporting the assessment that languages are not bounded entities but sociocultural and ideological constructions, this article explores commercial advertisements in France, which are subject to language policies assuming that ‘French’ is easily separable from ‘foreign languages’. Employing the Bakhtinian‐influenced notion of bivalency developed by Woolard (1998), the article argues for a special consideration of mixed‐language advertising in France, rooted not only in linguistic form, but also in the specific contextual tension produced by the socio‐political statuses of French and English. The resulting creativity challenges the monolectal assumptions within French language management, indicating a clash of segregational language ideology with integrational language practices. The article further argues that this language mixing is bidirectional, as advertisements may both erase and emphasise the assumed boundaries between codes. 相似文献
316.
Nagarajan N. Renuga Teixeira Aurora A. C. Silva Sandra T. 《Population research and policy review》2021,40(2):187-210
Population Research and Policy Review - The issue of population ageing is no longer exclusively centred on developed countries. Empirical studies have proven that the rise in the proportion of the... 相似文献
317.
To perform variable selection in expectile regression, we introduce the elastic-net penalty into expectile regression and propose an elastic-net penalized expectile regression (ER-EN) model. We then adopt the semismooth Newton coordinate descent (SNCD) algorithm to solve the proposed ER-EN model in high-dimensional settings. The advantages of ER-EN model are illustrated via extensive Monte Carlo simulations. The numerical results show that the ER-EN model outperforms the elastic-net penalized least squares regression (LSR-EN), the elastic-net penalized Huber regression (HR-EN), the elastic-net penalized quantile regression (QR-EN) and conventional expectile regression (ER) in terms of variable selection and predictive ability, especially for asymmetric distributions. We also apply the ER-EN model to two real-world applications: relative location of CT slices on the axial axis and metabolism of tacrolimus (Tac) drug. Empirical results also demonstrate the superiority of the ER-EN model. 相似文献
318.
Product bundling has become increasingly prevalent not only in consumer goods but also in the industrial sector. We study a purchasing problem in which a buyer must obtain necessary numbers of various stock items from a variety of vendors who charge different prices, have limited capacities and different levels of quality, and offer bundled products at discounted prices. We examine relationships among different bundling scenarios and show that the most general scenario is one in which free items are given to the buyer when sufficient quantities are purchased. We develop a mixed integer linear program that finds the purchasing strategy for the buyer that minimizes the total purchase cost. We present computational results which indicate that the problem is very tractable to solve optimally on a personal computer with standard optimization software. Finally, three extensions of the model are discussed. 相似文献
319.
The conversion of multivariate data analysis into information that managers can readily use in their decision making has always been a challenging task. In this paper we provide a parallel axis representation of multivariate data and demonstrate how this representation may be used as a tool for implementing the results of data envelopment analysis. We use an analysis of the efficiency of electricity generating plants to illustrate the technique. 相似文献
320.
In recent decades, quantile regression has received much more attention from academics and practitioners. However, most of existing computational algorithms are only effective for small or moderate size problems. They cannot solve quantile regression with large-scale data reliably and efficiently. To this end, we propose a new algorithm to implement quantile regression on large-scale data using the sparse exponential transform (SET) method. This algorithm mainly constructs a well-conditioned basis and a sampling matrix to reduce the number of observations. It then solves a quantile regression problem on this reduced matrix and obtains an approximate solution. Through simulation studies and empirical analysis of a 5% sample of the US 2000 Census data, we demonstrate efficiency of the SET-based algorithm. Numerical results indicate that our new algorithm is effective in terms of computation time and performs well for large-scale quantile regression. 相似文献