A Statistical Model to Investigate the Reproducibility Rate Based on Replication Experiments

The reproducibility crisis, that is, the fact that many scientific results are difficult to replicate, pointing to their unreliability or falsehood, is a hot topic in the recent scientific literature, and statistical methodologies, testing procedures and p‐values, in particular, are at the centre of the debate. Assessment of the extent of the problem–the reproducibility rate or the false discovery rate–and the role of contributing factors are still an open problem. Replication experiments, that is, systematic replications of existing results, may offer relevant information on these issues. We propose a statistical model to deal with such information, in particular to estimate the reproducibility rate and the effect of some study characteristics on its reliability. We analyse data from a recent replication experiment in psychology finding a reproducibility rate broadly coherent with other assessments from the same experiment. Our results also confirm the expected role of some contributing factor (unexpectedness of the result and room for bias) while they suggest that the similarity between original study and the replica is not so relevant, thus mitigating some criticism directed to replication experiments.     

Simulating the Evolution of the Implied Distribution

Motivated by the implied stochastic volatility literature (Britten–Jones and Neuberger, forthcoming; Derman and Kani, 1997; Ledoit and Santa–Clara, 1998) this paper proposes a new and general method for constructing smile–consistent stochastic volatility models. The method is developed by recognising that option pricing and hedging can be accomplished via the simulation of the implied risk neutral distribution. We devise an algorithm for the simulation of the implied distribution, when the first two moments change over time. The algorithm can be implemented easily, and it is based on an economic interpretation of the concept of mixture of distributions. It can also be generalised to cases where more complicated forms for the mixture are assumed.     

Issues in the estimation and application of latent structure models of choice

Our paper provides a brief review and summary of issues and advances in the use of latent structure and other finite mixture models in the analysis of choice data. Focus is directed to three primary areas: (1) estimation and computational issues, (2) specification and interpretation issues, and (3) future research issues. We comment on what latent structure models have promised, what has been, to date, delivered, and what we should look forward to in the future.     

—种BCH码的新型译码方法及其FPGA器件实现

介绍了一种新型的BCH码的译码方法,并给出了该译码算法的FPGA器件实现方法。与传统的译码算法相比,该算法具有译码速度快、硬件实现复杂度低等优点,从而使得该译码器具有速度快、体积小、性能稳定等特点。     

基于物联网的自动入库管理系统及其应用研究

利用RFID电子标签作为产品识别的手段,利用物联网来获取入库产品的详细信息并自动生成入库单,从而提出了基于物联网的自动入库管理系统的基本原理,对系统的结构和功能进行了分析,并通过应用实例说明了系统的优点。     

文学符号特殊性对哈姆雷特行为的解码

语言学先驱索绪尔认为语言是一个符号系统,社会中一切有意义的东西都有符号,都可以从符号学的观 点进行研究。可从文学符号的特殊性来探讨莎士比亚悲剧《哈姆雷特》中主人公哈姆雷特的行为。     

高职学生思想政治工作重点的探讨

当前高职学生的行为规范,与当代大学生应有的良好形象相比尚有较大差距。如不加大这方面的教育力度,不但会影响高职学生本人的前途,而且势必影响高职学校的发展。作者从高职院区党支部书记的视点出发,有针对性地提出了一系列改进高职学生思想政治工作的措施建议。     

A Note on Minimax Mixture of Distributions Free Procedure for Inventory Model with Variable Lead Time

In recent papers, Moon and Choi (1998) and Hariga and Ben-Daya (1999)considered a continuous review inventory model with a mixture of backordersand lost sales in which the lead time, the order quantity, and the reorder pointare decision variables was studied. Moreover, they also develop a minimaxdistribution free procedure for the problem. While the demands of differentcustomers are not identical in the lead time, then we can't only use a singledistribution (such as Moon & Choi (1998) and Hariga & Ben-Daya (1999))to describe the demand of the lead time. Hence, we correct and extend the modelof Moon and Choi (1998) and Hariga and Ben-Daya (1999) by considering thelead time demand with the mixture of distributions. In addition, we also applythe minimax mixture of distributions free approach to the model by simultaneouslyoptimizing the order quantity, the reorder point, and the lead time to devise a practical procedure which can be used without specific information on demand distribution.     

基于可持续发展的区域矿产资源配置问题研究

本文基于矿产资源的有限性和不可再生性,确立了资源优化配置的多目标准则;在全面分析影响区域矿产资源优化配置的社会经济发展需求因素,区域资源基础及潜力因素,资源开发利用的能力和水平因素,区域生态环境承载力因素,资源安全储备因素,区域外资源可供性因素,配套资源及基础设施支持因素的基础上,建立了区域矿产资源合理开发规模和速度的评价指标体系和分析计算模型;就河北省矿产资源的合理开发问题进行了具体的实证分析,研究了多目标准则下区域矿产资源开发和利用在时间维度上的优化配置问题,为合理规划和调整区域矿产资源开发利用战略提供了有益参考。     

Sovereign Risk Contagion in East Asia: A Mixture of Time-Varying Copulas Approach

This study analyzes sovereign risk contagion between four East Asian economies (China, Hong Kong, Japan, and Korea) and its structural changes through the Global Financial Crisis (GFC) and the European Debt Crisis (EDC) by applying the mixture of time-varying copulas to those economies’ credit default swap (CDS) spreads.

This article first finds a strong contagion from the US and PIIGS economies to the East Asian sovereign CDS markets and intraregional contagion within the East Asian markets. Second, the impact of contagion is different according to whether it is measured by the linear (Gaussian) or the upper tail dependence. Third, Japan plays an important role in increasing the linear dependence whereas China and Korea are crucial in terms of the upper tail dependence. Lastly, the GFC has structurally increased the linear dependence but not the upper tail dependence between the East Asian sovereign CDS markets.