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991.
Peter K. Mackie Rosemary D.F. Bromley Alison M.B. Brown 《International journal of urban and regional research》2014,38(5):1884-1903
Informal trading in the global South, particularly in Latin America, is the subject of revanchist urban policy and yet few studies have examined the longer‐term impacts of such intolerant policies on traders. This article explores the evolution and impacts of revanchist policies directed at informal traders in the Andean city of Cusco. It makes two key contributions. First, it documents a shift from early revanchist policies to a post‐revanchist era where policies have become more tolerant of informal traders. However, contemporary policies fall short of a supportive environment for informal trading, hence the authors recommend changes that will ensure informal traders can access the city's streets and become an accepted part of the urban fabric. Second, given the lack of theoretical attention given to the impacts of revanchism, a battlegrounds framework is developed, consisting of spatial, political, economic and socio‐cultural battlegrounds. This framework provides a comprehensive insight into the complex set of interactions that exist between informal traders and the state. It is hoped that the framework will provide a tool for further research into the highly damaging impacts of revanchism across the globe. 相似文献
992.
Pierre Picard 《The GENEVA Risk and Insurance Review》2014,39(2):153-175
We extend the Rothschild-Stiglitz (RS) insurance market model with adverse selection by allowing insurers to offer either non-participating or participating policies, that is, insurance contracts with policy dividends or supplementary calls for premium. It is shown that an equilibrium always exists in such a setting. Participating policies act as an implicit threat that dissuades deviant insurers who aim to attract low-risk individuals only. The model predicts that the mutual corporate form should be prevalent in insurance markets where second-best Pareto efficiency requires cross-subsidisation between risk types. 相似文献
993.
Iain L. MacDonald 《Revue internationale de statistique》2014,82(2):296-308
There is by now a long tradition of using the EM algorithm to find maximum‐likelihood estimates (MLEs) when the data are incomplete in any of a wide range of ways, even when the observed‐data likelihood can easily be evaluated and numerical maximisation of that likelihood is available as a conceptually simple route to the MLEs. It is rare in the literature to see numerical maximisation employed if EM is possible. But with excellent general‐purpose numerical optimisers now available free, there is no longer any reason, as a matter of course, to avoid direct numerical maximisation of likelihood. In this tutorial, I present seven examples of models in which numerical maximisation of likelihood appears to have some advantages over the use of EM as a route to MLEs. The mathematical and coding effort is minimal, as there is no need to derive and code the E and M steps, only a likelihood evaluator. In all the examples, the unconstrained optimiser nlm available in R is used, and transformations are used to impose constraints on parameters. I suggest therefore that the following question be asked of proposed new applications of EM: Can the MLEs be found more simply and directly by using a general‐purpose numerical optimiser? 相似文献
994.
Alvaro J. Name-Correa 《Review of Economic Design》2017,21(4):291-316
From experience, fund-raisers become more efficient solicitors. This paper offers a full characterization of the optimal solicitation strategy when there are learning economies. The characterization is recursive, and does not require equilibrium computations. Our main results are that (1) the fund-raiser may now solicit a “ net free-rider”—a donor whose contribution falls below the marginal solicitation cost; (2) the number of solicitations is non-monotonic in the learning rate; and (3) a solicitation technology with high overhead but low marginal costs is likely to be optimal if income distribution in the population is relatively homogenous. The complementary case with a decreasing returns to scale technology is also considered. 相似文献
995.
996.
In recent years, a growing number of small-to-medium-enterprises are embracing wind turbine projects not only as part of their cost reduction strategy but also to actively play their part in the global fight against climate change. However, it would appear there are currently limited empirical studies carried out in this emerging industry. This case study analyses the cost effectiveness of one such wind turbine initiative by a company in the Republic of Ireland, who invested in a 300 kW embedded wind turbine project at the end of 2013. The research methodology which is primarily a case study analysis included comparing historical electricity utility bills which allowed the 2013 quantity of electrical energy units imported, i.e. the year before the turbine was installed to be compared with the 2014 value, i.e. the year after the turbine was installed. Numerous site visits were undertaken over a four-year period, during which electric meter readings were recorded and stored. The findings of this piece of research indicate that the installation of the embedded wind turbine had minimal positive effect on the annual electricity costs for the company. Indeed the turbine appears to have significant negative effects such as a need for an increased maximum import capacity and also it appeared to contribute to a deteriorating utility power factor. While the aesthetic nature of the on-site turbine seemed to create a positive image of the company, it would appear that caution should be exercised when business owners select alternative energy providers who claim to be experts in the energy field but may have limited knowledge in this area of wind energy, which as of yet has minimal robust research into all aspects of its benefits/attributes. 相似文献
997.
Stephen F. Young Lisa A. Steelman 《International Journal of Human Resource Management》2017,28(6):797-824
This study examined the process by which individuals become engaged with their jobs by integrating seminal engagement theory. More specifically, we suggest that an individual factor (i.e. autotelic personality) and two contextual factors (i.e. feedback environment, job autonomy) interact to predict work engagement through three critical psychological states – namely availability, meaningfulness, and safety. This moderated mediation framework was tested using a cross section of the US population (n = 284); data were collected at two points in time with 3 months in between. Availability and meaningfulness mediated the relationship between autotelic personality and work engagement. Autotelic personality’s indirect effect on work engagement through meaningfulness and safety was conditional such that the nature of feedback environment’s effect depended on job autonomy level. Theory and practice implications are discussed. 相似文献
998.
I. M. Aizinova 《Studies on Russian Economic Development》2017,28(4):450-457
The first part of this published paper has provided a brief assessment of the demographic situation in the world and considers the problems of the health protection of elderly age groups and ensuring of their level of income and material well-being through the state pension system and their own work activities, as well as measures for protecting the interests of elderly people in the consumer sector. The shortcomings of the adopted strategy of action for the benefit of the older generation in the Russian Federation until 2025 have been discussed. The second part of this article will be be published in a forthcoming issue of this journal. 相似文献
999.
This research introduces the multi-product capacitated facility location problem with general production and building costs (MP-CFLPGC). The MP-CFLPGC extends previous problems found in the literature by including multiple products and general production and building cost functions that allow the modeling of different behaviors like economies of scale and congestion. The MP-CFLPGC is formulated as a mixed integer linear program (MILP). To evaluate the performance of the proposed formulation we analyze the results of a commercial optimizer on a set of 288 randomly generated test instances that resemble the Colombian cement industry supply chain. After one hour the optimizer achieved an optimality gap of 1.0 % or less in 55 % out of the 288 test instances. On average the optimality gap was 3.57 %. Additionally, we propose a randomized mathematical-programming-based heuristic for the test instances where the MILP formulation presents significantly high optimality gaps. 相似文献
1000.
S. V. Kiselev A. S. Strokov A. Yu. Belugin 《Studies on Russian Economic Development》2016,27(5):548-556
This paper analyzes the possible impact of irrigation on the development of agriculture in the Volga River Basin and Black Sea Basin. Scenarios of the development of agriculture in Russia up to 2030 under the conditions of the expansion of irrigation and persistence of the current situation with irrigation have been calculated and analyzed based on the IMPACT-3 econometric partial equilibrium model. 相似文献