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The joint and marginal distributions of generalized order statistics based on an arbitrary distribution function are established in terms of the lexicographic distribution function. Furthermore, we show that generalized order statistics and the corresponding number of ties form a two-dimensional Markov chain.  相似文献   
74.
This paper explores the implications of different labour market adjustment formulations for the analysis of trade liberalization across different sectors and households in the Vietnamese economy using computable general equilibrium (CGE) models. The model is calibrated to a model admissible Vietnamese data set for 1997.We use five different adjustment cost treatments in analyzing the effects of trade liberalization in Vietnam. We compare simulation results from each and show how different treatments can significantly affect the distributional impacts of policy reforms, such as the trade liberalization. First, labour is treated as fully mobile across all sectors in the economy. Second, the sectors of economy are broken down into the two blocks of agricultural and industrial-service sectors and labour markets are treated as segmented by sector block. No mobility of labour between blocks is allowed while labour within each sector block remains fully mobile. The third is the same as the second, but movement within each agricultural and industrial-service sector block involves transactions costs. In the fourth, mobility of workers from the agricultural to industrial-service sectors and vice versa is possible with transactions costs. Finally, we calibrate the model with unemployment but no adjustment costs for labour reallocation to explore how model results differ in terms of adjustments in the labour market and welfare effects.Our results indicate significant differences in the impacts from trade liberalization across these cases. The redistributional impact of trade liberalization is sharper against poor rural households with segmented labour markets and with transactions costs, while aggregate efficiency gains are similar to no adjustment cost analyses. The conclusion is the choice of model structure for labour markets is crucially important for the perceived distributional impacts of trade liberalization.  相似文献   
75.
Detection of heavy metals at trace or higher levels in foods and food ingredients is not unexpected given the widespread unavoidable presence of several metals in nature, coupled with advancement in analytical methods and lowering limits of detection. To assist risk managers with a rapid risk assessment when facing these situations, a metal dietary exposure screening tool (MDEST) was developed. The tool uses food intake rates based on the National Health and Nutrition Examination Survey 2005–2010 consumption data for the U.S. population two+ years and up and for infants age six months to <two years based on the Nestlé Feeding Infants and Toddlers Study, and existing exposure limits for several frequently detected metals (e.g., inorganic arsenic, cadmium, chromium, lead, and mercury). The tool has data entry fields for detected concentrations and includes algorithms that combine metal levels with consumption data to generate screening‐level exposure estimates, which it then compares to MDEST assigned default portions of the exposure limits in the risk characterization module. As a screening‐level tool, the risk assessment output is intentionally conservative, public health protective, and useful for a rapid assessment to set aside issues that are not of concern. Issues that cannot be readily resolved using this screening tool will need to be further evaluated with more refined input data that are tailored to the specific question or situation under consideration.  相似文献   
76.
In the literature on political support, much empirical effort has been devoted to the link between economic performance and satisfaction with democracy. Nevertheless, analyses are often inconclusive in their findings. This study tries to renew the interest in the topic by using multilevel models to analyse 108 surveys from the repeated cross-sectional Eurobarometer data between 1985 and 2013, and focuses on southern European countries which share political and economic characteristics. Thus, the article links economic trends to changes in satisfaction with democracy in Greece, Italy, Portugal and Spain, also emphasizing the relevance of transformations in their political systems. The results demonstrate that low economic performance seems to negatively affect citizens’ satisfaction with democracy in the four countries and across the whole period analysed. This also holds true for different model specifications and when other potential factors such as the format and the performance of the institutional context are controlled for. By providing empirical evidence based on a longitudinal analysis, this article contributes to the wider debate on how economic conditions influence opinions about democracy.  相似文献   
77.
The Multidimensional Assignment Problem (MAP) is a higher dimensional version of the linear assignment problem, where we find tuples of elements from given sets, such that the total cost of the tuples is minimal. The MAP has many recognized applications such as data association, target tracking, and resource planning. While the linear assignment problem is solvable in polynomial time, the MAP is NP-hard. In this work, we develop a new approach based on the Cross-Entropy (CE) methods for solving the MAP. Exploiting the special structure of the MAP, we propose an appropriate family of discrete distributions on the feasible set of the MAP that allow us to design an efficient and scalable CE algorithm. The efficiency and scalability of our method are proved via several tests on large-scale problems with up to 5 dimensions and 20 elements in each dimension, which is equivalent to a 0–1 linear program with 3.2 millions binary variables and 100 constraints.  相似文献   
78.
The Italian National Statistical Office is implementing a new project for computing sub-national Purchasing Power Parities (PPPs) on a regular basis, which is based on an appropriate use of existing Consumer Price Index (CPI) data and new sources of data. Concerning the use of CPI data, in this paper the role of the Country Product Dummy (CPD) method for compiling sub-national PPPs at Basic–Heading (BH) level is analysed together with the specific issues that arise in this context, such as the need to take spatial autocorrelation among price relatives into account. The results of various experiments based on CPI data concerning 7 BHs and 19 Italian regional chief towns are presented and discussed with the aim of exploring the performance of various CPD models and analysing to what extent the type and characteristics of the data affect the estimates obtained. The statistical uncertainty associated with the ranks derived from the regional PPPs was then calculated by means of a simulation procedure. Our findings prove to be interesting and confirm that methods and CPI data for spatial comparisons are reciprocally influenced.  相似文献   
79.
The Vietnamese government aims to expand the scale of Naturland certified organic production in integrated shrimp–mangrove farming systems across the coast of Ca Mau province by 2015. In doing so the division between public and private regulation has become blurred. We analyze the government's goal by examining the regulatory challenges of using organic certification as a means of linking farm-level management to the sustainability of coastal (mangrove) landscapes. The results show the importance of farmer perceptions of sustainable farm and landscape management, fair benefit sharing mechanisms in the certified value chain, and legitimate private sector-led auditing. We conclude that in order to overcome conflicts of interest and legitimate representation in organic certification, the social and economic conditions of production require regulatory intervention from provincial and local level government. To achieve benefits beyond the scale of the farm, the role of shrimp producers should be redefined as partners in rather than targets of regulation.  相似文献   
80.
Denote the integer lattice points in the N  -dimensional Euclidean space by ZNZN and assume that (Xi,Yi)(Xi,Yi), i∈ZNiZN is a mixing random field. Estimators of the conditional expectation r(x)=E[Yi|Xi=x]r(x)=E[Yi|Xi=x] by nearest neighbor methods are established and investigated. The main analytical result of this study is that, under general mixing assumptions, the estimators considered are asymptotically normal. Many difficulties arise since points in higher dimensional space N?2N?2 cannot be linearly ordered. Our result applies to many situations where parametric methods cannot be adopted with confidence.  相似文献   
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