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171.
《Journal of Policy Modeling》2019,41(3):522-536
US trade policy in the Trump administration is protectionist, raising tariffs outside of WTO rules, threatening trade wars, withdrawing from existing trade agreements, and negotiating new bilateral trade deals rather than free trade agreements. The reaction of the rest of the world has been to support the WTO rules-based trading system and to pursue new and expanded regional trade agreements that do not include the US. The result may be US disengagement from the world trading system, with countries diverting trade around the US. We use a global computable general equilibrium (CGE) model to analyze changes in trade and production patterns for a variety of scenarios, including US trade wars. We find that adjustment to US disengagement is feasible—the changes in trade shares as countries divert trade are modest and achievable, with very little impact on the volume of global trade. If the US engages in trade wars with major partners, the best response for other trade partners is to sit out the trade war, accept higher US tariffs, and gain markets from global trade diversion around the US. Finally, because of indirect effects, widespread tariffs fail to benefit the protected sectors—a fallacy of composition in a protectionist trade policy. 相似文献
172.
Marta Blangiardo 《Journal of applied statistics》2014,41(10):2312-2322
The Eurovision Song Contest is an annual musical competition held among active members of the European Broadcasting Union since 1956. The event is televised live across Europe. Each participating country presents a song and receive a vote based on a combination of tele-voting and jury. Over the years, this has led to speculations of tactical voting, discriminating against some participants and thus inducing bias in the final results. In this paper we investigate the presence of positive or negative bias (which may roughly indicate favouritisms or discrimination) in the votes based on geographical proximity, migration and cultural characteristics of the participating countries through a Bayesian hierarchical model. Our analysis found no evidence of negative bias, although mild positive bias does seem to emerge systematically, linking voters to performers. 相似文献
173.
研究了碎纸片的拼接复原问题,建立了合理有效的碎纸片拼接复原的数学模型;给出了数学软件实现自动拼接的具体算法;结合人工拼接得出复原图片;最后,对所给的拼接方法提出了改进方向. 相似文献
174.
Quasi-likelihood nonlinear models (QLNMs) are an extension of generalized linear model and include a widen class of models as special cases. This article investigates some diagnostic methods in QLNMs. An equivalency between a case-deletion model and a mean-shift outlier model in QLNM is established. Two simulation study and a real dataset are used to illustrate the proposed diagnostic methods. 相似文献
175.
Data sets with excess zeroes are frequently analyzed in many disciplines. A common framework used to analyze such data is the zero-inflated (ZI) regression model. It mixes a degenerate distribution with point mass at zero with a non-degenerate distribution. The estimates from ZI models quantify the effects of covariates on the means of latent random variables, which are often not the quantities of primary interest. Recently, marginal zero-inflated Poisson (MZIP; Long et al. [A marginalized zero-inflated Poisson regression model with overall exposure effects. Stat. Med. 33 (2014), pp. 5151–5165]) and negative binomial (MZINB; Preisser et al., 2016) models have been introduced that model the mean response directly. These models yield covariate effects that have simple interpretations that are, for many applications, more appealing than those available from ZI regression. This paper outlines a general framework for marginal zero-inflated models where the latent distribution is a member of the exponential dispersion family, focusing on common distributions for count data. In particular, our discussion includes the marginal zero-inflated binomial (MZIB) model, which has not been discussed previously. The details of maximum likelihood estimation via the EM algorithm are presented and the properties of the estimators as well as Wald and likelihood ratio-based inference are examined via simulation. Two examples presented illustrate the advantages of MZIP, MZINB, and MZIB models for practical data analysis. 相似文献
176.
Ritesh Khunyakari 《Children & Society》2021,35(4):613-629
The conceptualizations about children and childhoods enrich our understanding of adult–child interactions, educational practice, policy and child-welfare interventions. This study explored 42 cultural metaphors drawn from diverse socio-economic, geographical and linguistic settings to construct Indian childhoods. The paper reports an interpretative analysis of reconstructions leading to a typology of metaphors-in-use. The conceptual-analytical exercise helped unpack nuances and contextual meanings of metaphors. The paper argues for richness and subtlety in theorising childhoods, which is multilayered, situated and intertwined with contextual issues and tensions. The study offers methodological, pedagogical and conceptual insights and proposes possibilities for using cultural tools into inquiring childhoods. 相似文献
177.
In this paper, we propose a model based on multivariate decomposition of multiplicative – absolute values and signs – components of asset returns. In the m-variate case, the marginals for the m absolute values and the binary marginals for the m directions are linked through a 2m-dimensional copula. The approach is detailed in the case of a bivariate decomposition. We outline the construction of the likelihood function and the computation of different conditional measures. The finite-sample properties of the maximum likelihood estimator are assessed by simulation. An application to predicting bond returns illustrates the usefulness of the proposed method. 相似文献
178.
Maengseok Noh Johan H.L. Oud Toni Toharudin 《Journal of Statistical Computation and Simulation》2019,89(9):1555-1573
Factor models, structural equation models (SEMs) and random-effect models share the common feature that they assume latent or unobserved random variables. Factor models and SEMs allow well developed procedures for a rich class of covariance models with many parameters, while random-effect models allow well developed procedures for non-normal models including heavy-tailed distributions for responses and random effects. In this paper, we show how these two developments can be combined to result in an extremely rich class of models, which can be beneficial to both areas. A new fitting procedures for binary factor models and a robust estimation approach for continuous factor models are proposed. 相似文献
179.
The prediction error for mixed models can have a conditional or a marginal perspective depending on the research focus. We introduce a novel conditional version of the optimism theorem for mixed models linking the conditional prediction error to covariance penalties for mixed models. Different possibilities for estimating these conditional covariance penalties are introduced. These are bootstrap methods, cross-validation, and a direct approach called Steinian. The behavior of the different estimation techniques is assessed in a simulation study for the binomial-, the t-, and the gamma distribution and for different kinds of prediction error. Furthermore, the impact of the estimation techniques on the prediction error is discussed based on an application to undernutrition in Zambia. 相似文献
180.
While the negative impact of child‐raising and caring on women's career progression in academia is well‐established, less is known about the role of academic women's lived experiences of maternity leave as an institutional practice. This article presents the findings of a qualitative study of the lived experiences of female academics and researchers in an Irish university. The analysis intrinsically links organizational structures and problems with the lived and felt dimensions of work. The findings point to the need for better structural accommodations for maternity leave which address the relationship between caring and career disadvantage within academia. The article adds to existing literature on the intersection of motherhood and academia by unpicking the specific role of maternity leave as both a lived experience and an institutional practice that can reinforce gender inequalities in academia. 相似文献