What’s in a yardscape? A case study of emergent ecosystem services and disservices within resident yardscape discourses in Minnesota

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...     

Ageing Population: Identifying the Determinants of Ageing in the Least Developed Countries

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...     

An elastic-net penalized expectile regression with applications

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.     

Decisions to Outsource Information Systems Functions: Testing a Strategy-Theoretic Discrepancy Model

In recent years, the decision to outsource information systems (IS) functions has become a viable strategic alternative in managing the increasingly complex IS functions. In this study, the IS outsourcing phenomenon is conceptualized as a strategic decision in the organization. Drawing on resource-based theories, resource dependence theories, and other theories of strategic management, a discrepancy model of this decision is developed. Relationships between a number of strategy-theoretic factors and the IS outsourcing decision are hypothesized. These factors include IS resource performance discrepancies manifested in the form of gaps in information quality, IS support quality, IS cost effectiveness and financial performance, as well as the strategic orientation of the firm. Results of the study indicate that, while cost consideration and the firm's financial performance are not associated with the IS outsourcing decision, difficulties in providing good information outputs and IS support services are associated with the decision. Overall, the findings suggest that the current trend toward outsourcing represents a continuing evolution of the IS function as it attempts to fulfill its traditional mission of providing high quality information resource to the firm. When the performance of the delivered resource begins to slip in the current environment of rising expectation and technological complexity, outsourcing may become a strategic response of necessity. The paper concludes with a discussion of the implications of the results for practicing managers and suggestions for future research.     

Vendor Selection with Bundling*

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.     

A Path Analytic Model of a Theory of Quality Management Underlying the Deming Management Method: Preliminary Empirical Findings*

Despite the impact that Deming and his 14 Points have had on the practice of quality management, empirical support for the effectiveness of the Deming Management Method has not advanced beyond the presentation of anecdotal, case-study evidence. In part, this is because theory to guide the conduct of empirical research has not been available. Only recently has such a theory of quality management to describe and explain the effectiveness of the Deming Management Method been articulated in the literature. This paper continues the journey of theory development; it reports the results of an exploratory empirical analysis of an articulated theory of quality management underlying the Deming Management Method. The constructs in the proposed theory are operationalized using measurement statements developed by the World-Class Manufacturing research project team at the University of Minnesota and Iowa State University. Path analysis is applied to the World-Class Manufacturing project data to explore the empirical strength of relationships advanced in the theory. The path analytic results provide support for several of the proposed relationships in the theory, and more importantly, suggest a number of new relationships which have not heretofore been proposed.     

Fifty Years After the Social Indicators Movement: Has the Promise Been Fulfilled?

In spite of its currency both in academic research and political rhetoric, there are numerous attempts to define and conceptualize the social cohesion concept but there has been paid little attention to provide a rigorous and empirically tested definition. There are even fewer studies that address social cohesion in a framework of cross-cultural validation of the indicators testing the equivalence of the factorial structure across countries. Finally, as far as we know there is no study that attempt to provide an empirically tested multilevel definition of social cohesion specifying a Multilevel Structural Equation Model. This study aims to cover this gap. First, we provide a theoretical construct of social cohesion taking into account not only its multidimensionality but also its multilevel structure. In the second step, to test the validity of this theoretical construct, we perform a multilevel confirmatory factor analysis in order to verify if the conceptual structure suggested in first step holds. In addition, we test the cross-level structural equivalence and the measurement invariance of the model in order to verify if the same multilevel model of social cohesion holds across the 29 countries analysed. In the final step, we specify a second-order multilevel CFA model in order to identify the existence of a general factor that can be called “social cohesion” operating in society that accounts for the surface phenomena that we observe.     

Destroyed by Slavery? Slavery and African American Family Formation Following Emancipation

This study introduces a new sample that links people and families across 1860, 1880, and 1900 census data to explore the intergenerational impact of slavery on black families in the United States. Slaveholding—the number of slaves owned by a single farmer or planter—is used as a proxy for experiences during slavery. Slave family structures varied systematically with slaveholding sizes. Enslaved children on smaller holdings were more likely to be members of single-parent or divided families. On larger holdings, however, children tended to reside in nuclear families. In 1880, a child whose mother had been on a farm with five slaves was 49 % more likely to live in a single-parent household than a child whose mother had been on a farm with 15 slaves. By 1900, slaveholding no longer had an impact. However, children whose parents lived in single-parent households were themselves more likely to live in single-parent households and to have been born outside marriage.