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Regression discontinuity designs have become popular in empirical studies due to their attractive properties for estimating causal effects under transparent assumptions. Nonetheless, most popular procedures assume i.i.d. data, which is unreasonable in many common applications. To fill this gap, we derive the properties of traditional local polynomial estimators in a fixed- G setting that allows for cluster dependence in the error term. Simulation results demonstrate that accounting for clustering in the data while selecting bandwidths may lead to lower MSE while maintaining proper coverage. We then apply our cluster-robust procedure to an application examining the impact of Low-Income Housing Tax Credits on neighborhood characteristics and low-income housing supply.

Business process models, while primarily intended for process documentation, communication, and improvement, are often also used as input for developing process-oriented software systems (Ouyang et al., 2009). Ensuring correctness, handling complexity, and improving reusability and maintainability of business process models are important for all these goals. The purpose of this paper is to propose an aspect-oriented business process modeling and correctness controlling method based on Petri nets to satisfy these goals.

The aspect-oriented paradigm provides a proper mechanism to modularization, and thus reduces the complexity of models, and also improves reusability and maintainability. However, weaving aspects into base processes may bring in mistakes or errors. To ensure correctness of modeling, this paper presents a formal approach to modeling aspect-oriented business processes and a method to ensure modeling correctness. Petri net is used as the process modeling language and its analysis techniques are applied to analyze the correctness of modeling. Two types of correctness, specifically, aspect-aspect correctness and base-aspect correctness are analyzed. A real banking process model is studied systematically in the case study to evaluate the approach and the performance assessments are conducted to show the cost and effect of the approach.

Designing aspect-oriented business process models help organizations reusing the model elements to reduce redundancy of their model repository, improving their maintainability, and supporting them to adapt to the changes of business requirements with flexible modeling. It is important to stress that the correctness of business process modeling is important in ensuring the quality of the models, especially in the safety-critical business domains, such as financial business domain.

In this paper, separation of concerns is used to separate the cross-cutting activities and core activities in accordance with the different functions of these activities, and an approach to modeling aspect-oriented business processes is proposed. First, the cross-cutting activities are encapsulated as aspects, while core business activities are modeled as base processes. Then, according to the correctness requirements of business process models, based on the weaving mechanisms of aspect-oriented approach, weaving correctness is defined. Weaving correctness controlling methods between multi-aspects and between aspects and base processes are designed. Errors or mistakes of aspect-oriented business process modeling are prevented during the procedure of modeling to ensure error-free business process modeling.

The purpose of this paper is to examine the relationship between the quality of different dimensions of institutional and economic growth in a panel of 15 member ECOWAS.

The study adopts Driscoll and Kraay′s nonparametric covariance matrix estimator, and the spatial error model to account for cross-section dependency, cross-country heterogeneity and spatial dependence inherent in empirical modelling, which has largely been ignored in previous studies. This is because, the likelihood that corruption and human capital cluster in space is very high because factors that affect these phenomena disperse across borders. Similarly, to test the threshold effect, the study adopts the more refined and more appropriate dynamic panel data which models a nonlinear asymmetric dynamics and cross-sectional heterogeneity, simultaneously, in a dynamic threshold panel data framework.

The empirical evidence supports findings by previous researchers that better-quality political and economic institutions can have positive effects on economic growth. Similarly, our results support a nonlinear relationship between political institutions and economic institution, confirming the “hierarchy of institution hypothesis” in ECOWAS. Specifically, the findings show that economic institutions will only have the desired economic outcome in ECOWAS, only when political institution is above a certain threshold.

Unlike previous studies which assume cross-sectional and spatial independence, the authors account for cross-section dependency and cross-country heterogeneity inherent in empirical modelling.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-10-2019-0630

The purpose of this paper is to analyse the phenomenon of wear resistance of some metals and alloys with allowance for the stiffness of their stressed‐strained state of the surface.

An original criterion (in the form of limiting deformation power density) of wear resistance on the basis of structure‐energy theory of friction is proposed. Experimental data on the wear resistance are generalized using the criterion for the conditions of hydroabrasive, impact‐abrasive and cavitational erosion.

The dependence of the criterion on stiffness coefficient of the stressed‐strained state of the surface of materials is demonstrated. It has been found that an increase of the stiffness results in the reduction in the energy capacity and wear resistance of both metals and alloys investigated.

The structure‐energy criterion can be used for choosing suitable frictional materials and to compare and estimate the theoretical considerations with experimental data.

The proposed structure‐energy approach allows systemizing the results of our analyses and the experimental data.

The paper analyses the prevalence of extreme and multidimensional poverty in line with the sustainable development agenda. In addition, the paper examines the drivers of extreme poverty while accounting for the potential spillover effect of poverty in the region.

The study adopts the pooled OLS with Discroll-Kraay robust standard errors to control for cross-sectional dependence. In addition, given the strong potential for endogeneity of poverty index, the authors also employ the generalized method of moments (GMM), which accounts for simultaneity and endogeneity problems, and the spatial error and lag models to control for all forms of spatial and temporal dependence since the factors that affect poverty disperse across borders.

The study finds that in addition to the traditional drivers of poverty (unemployment, low per capita GDP growth and public debt), poverty in Sub-Saharan Africa is a symptom of a deeper structural problem (lack of access to water and sanitation, high level of corruption and low level of financial development, and frequent economic busts). Likewise, the results from the spatial econometric specification show, consistently across all the specifications, that there is a substantial spillover effect of poverty across the region.

The main novelty of the paper is that the authors investigate the “economic shrinkage hypothesis,” and examined the potential negative spillover effect of poverty in the region.

This paper aims to analyze the welfare use of Turkish immigrants and natives in Germany. The authors ask whether the immigrant‐native gap in welfare use can be explained by observable characteristics, whether the mechanisms behind welfare dependence differ for Turkish immigrants and natives, and, finally, they compare the situation before and after the 2005 reform of the German welfare system.

Using data from the German Socio‐Economic Panel Study, the authors estimate linear probability models with random effects to investigate the correlates of transfer receipt for Turkish immigrants and natives.

Turkish immigrants have a higher propensity to use welfare benefits than natives. After controlling for general individual and household level characteristics, the difference in welfare receipt is statistically significant only for the group of second generation immigrants. The correlation of observable characteristics with welfare dependence differs significantly for the native and immigrant sample. The share of benefit recipients increased after the policy reform in 2005 for both immigrants and natives.

First, as human capital and particularly labor market status are important determinants of welfare use, training programs designed for the special needs of immigrants might support their labor market integration. Second, measures to ameliorate the integration of older people into the labor market might be particularly useful because the need for welfare benefits arises particularly at the 50‐60 age range.

This is the first study to investigate welfare use of Turkish immigrants after the German 2005 labor market policy reform.

A significant portion of academic research on marketing strategy focuses on how national brands of repeat-purchase goods are managed or should be managed. Surprisingly little consideration is given in this tradition to the extended role of geography, i.e. distance and space. For instance, manufacturers of brands in non-durable product categories are well aware of the fact that their national brands perform very different across domestic U.S. markets. This holds even for product categories with limited product differentiation. In this chapter, we outline various processes through which the influence of geography on performance of national brands materializes. We discuss a number of alternative explanations for the emergence and sustenance of spatial concentration of market shares. Several of these explanations are modeled empirically using data from the United States packaged goods industry. This chapter closes with avenues for further academic research on spatial aspects of the growth of new products.

Quasi‐static boundary value problems are formulated for the isothermal linear theory of swelling porous elastic soils in the case that the fluid is incompressible. First, some general theorems (uniqueness, reciprocal and continuous dependence) are established in the general case. Then, in the case that solid matrix is saturated with fluid and occupies a semi‐infinite cylinder of smooth cross section, a time‐weighted cross‐sectional area measure is used in order to establish spatial decay estimates for the quasi‐static solutions.

This paper gives a selective review on some recent developments of nonparametric methods in both continuous and discrete time finance, particularly in the areas of nonparametric estimation and testing of diffusion processes, nonparametric testing of parametric diffusion models, nonparametric pricing of derivatives, nonparametric estimation and hypothesis testing for nonlinear pricing kernel, and nonparametric predictability of asset returns. For each financial context, the paper discusses the suitable statistical concepts, models, and modeling procedures, as well as some of their applications to financial data. Their relative strengths and weaknesses are discussed. Much theoretical and empirical research is needed in this area, and more importantly, the paper points to several aspects that deserve further investigation.