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101.
In this paper, we aim to design a monetary policy for the euro area that is robust to the high degree of model uncertainty at the start of monetary union and allows for learning about model probabilities. To this end, we compare and ultimately combine Bayesian and worst‐case analysis using four reference models estimated with pre–European Monetary Union (EMU) synthetic data. We start by computing the cost of insurance against model uncertainty, that is, the relative performance of worst‐case or minimax policy versus Bayesian policy. While maximum insurance comes at moderate costs, we highlight three shortcomings of this worst‐case insurance policy: (i) prior beliefs that would rationalize it from a Bayesian perspective indicate that such insurance is strongly oriented towards the model with highest baseline losses; (ii) the minimax policy is not as tolerant towards small perturbations of policy parameters as the Bayesian policy; and (iii) the minimax policy offers no avenue for incorporating posterior model probabilities derived from data available since monetary union. Thus, we propose preferences for robust policy design that reflect a mixture of the Bayesian and minimax approaches. We show how the incoming EMU data may then be used to update model probabilities, and investigate the implications for policy. (JEL: E52, E58, E61)  相似文献   
102.
103.
Overview of Recent Developments in Ecotoxicological Risk Assessment   总被引:1,自引:1,他引:1  
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104.
Quasiextinction Probabilities as a Measure of Impact on Population Growth   总被引:3,自引:0,他引:3  
A probabilistic language based on stochastic models of population growth is proposed for a standard language to be used in environmental assessment. Environmental impact on a population is measured by the probability of quasiextinction. Density-dependent and independent models are discussed. A review of one-dimensional stochastic population growth models, the implications of environmental autocorrelation, finite versus "infinite" time results, age-structured models, and Monte Carlo simulations are included. The finite time probability of quasiextinction is presented for the logistic model. The sensitivity of the result with respect to the mean growth rate and the amplitude of environmental fluctuations are examined. Stochastic models of population growth form a basis for formulating reasonable criteria for environmental impact estimates.  相似文献   
105.
The following article by Keith Whyte represents the first of occasionally reprinted publications that are relevant to important historical events in the field of gambling studies. This article describes the act that led to the formation of the National Gambling Impact Study Commission. This Commission released its findings to the President and Congress of the United States during June of 1999.  相似文献   
106.
This paper identifies partner selection criteria in a sample of UK international joint ventures with Western European, US and Japanese partners. Rankings of selection criteria are derived for the sample using a typology that distinguishes between task-related and partner-related selection criteria. The most important task-related criteria are found to be access to knowledge of local market, access to distribution channels, access to links with major buyers and access to knowledge of local culture. The most important partner-related selection criteria are trust between the top management teams, relatedness of partner's business and reputation. A parsimonious set of selection criteria for the sample is provided by means of factor analysis. Hypotheses are tested on the relationship between the relative importance of selection criteria and a number of characteristics of the sample—partner nationality, industry of the joint ventures, joint-venture purpose, geographical location of the venture, initial approach for joint-venture formation and relative partner size. The greatest variation in the relative importance of selection criteria occurs with the geographic location of the joint venture.  相似文献   
107.
This paper investigates the interaction between the economics of production and imperfections in the production process. Specifically, this paper is the first to devise a model in an attempt to provide managers with guidelines to choose the appropriate production run times to buffer against both the production of defective items and stoppages occurring due to machine breakdowns. In addition to providing several structural properties of the model, we show that a manager will always incur a cost penalty when (s)he uses the results of two oft‐cited models‐the EMQ (Economic Order/Manufacturing Quantity) and the NR‐E (No‐Resumption, Exponential machine breakdown)‐to determine production run times.  相似文献   
108.
Establishing that there is no compelling evidence that some population is not normally distributed is fundamental to many statistical inferences, and numerous approaches to testing the null hypothesis of normality have been proposed. Fundamentally, the power of a test depends on which specific deviation from normality may be presented in a distribution. Knowledge of the potential nature of deviation from normality should reasonably guide the researcher's selection of testing for non-normality. In most settings, little is known aside from the data available for analysis, so that selection of a test based on general applicability is typically necessary. This research proposes and reports the power of two new tests of normality. One of the new tests is a version of the R-test that uses the L-moments, respectively, L-skewness and L-kurtosis and the other test is based on normalizing transformations of L-skewness and L-kurtosis. Both tests have high power relative to alternatives. The test based on normalized transformations, in particular, shows consistently high power and outperforms other normality tests against a variety of distributions.  相似文献   
109.
How Latino youth cope with stressors may have implications for their adjustment. We examined how a temperamental characteristic (effortful control) and a contextual factor (economic hardship) were associated with Latino youth's coping. Individual differences in effortful control, a core facet of self‐regulation, may contribute to coping as effortful control is consistently linked to adaptive behaviors during adolescence. We examined relations of effortful control and economic hardship to active coping in a sample of Mexican‐origin youth (= 674) across three time points (fifth to ninth grades). Although economic hardship negatively predicted coping and effortful control, effortful control positively predicted coping (controlling for prior levels). Findings support a resilience perspective by suggesting that effortful control may contribute to coping and thus counteract the negative effects of economic hardship.  相似文献   
110.
Sonoran Desert habitat in southern Arizona is increasingly altered by urban development near metropolitan areas. Understanding how reptiles respond in these impacted habitats is critical to conservation efforts to retain intact biotic communities, especially those with a high diversity of reptile species. We surveyed snakes at one impacted site on the northern edge of the Phoenix metropolitan area in desert/urban interface, and at another site in a desert/rural interface near Florence, Arizona. The site near Phoenix was lower in species richness (15 spp.), and evenness: two snake species accounted for 75 % of all snakes encountered (total = 420). The site near Florence was higher in species richness (19 spp.), and a more even community: no species accounted for more than 20 % of snakes encountered (total = 594). Sampling methodology had a strong influence on species richness and abundance of snakes at the respective sites: road riding, coverboards, and traps each provided evidence of unique species missed by other methods. These results were compared with inventories at three other sites in the central Sonoran Desert of Arizona, and are consistent with the view that the impacted site near Phoenix is uneven, potentially as a result of a single species reacting to shifts in prey availability.  相似文献   
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