A note on stable limit theory for the OLSE with non usual rates and the heteroskedasticity robust Wald test

We are occupied with an example concerning the limit theory of the ordinary least squares estimator (OLSE) when the innovation process of the regression has the form of a martingale transform the iid part of which lies in the domain of attraction of an α-stable distribution, the scaling sequence has a potentially diverging truncated α-moment, and the regressor process has a potentially divergent truncated second moment. We obtain matrix rates that reflect the stability parameter as well as the slow variations present in the aforementioned sequences, and stable limits. We also derive asymptotic exactness, consistency, and local asymptotic unbiasedness under appropriate local alternatives for a heteroskedasticity robust Wald test based on subsampling. The results could be useful for inference on the factor loadings in an instance of the APT model.     

Robust Bayesian prediction under a general linear-exponential posterior risk function and its application in finite population

We consider robust Bayesian prediction of a function of unobserved data based on observed data under an asymmetric loss function. Under a general linear-exponential posterior risk function, the posterior regret gamma-minimax (PRGM), conditional gamma-minimax (CGM), and most stable (MS) predictors are obtained when the prior distribution belongs to a general class of prior distributions. We use this general form to find the PRGM, CGM, and MS predictors of a general linear combination of the finite population values under LINEX loss function on the basis of two classes of priors in a normal model. Also, under the general ε-contamination class of prior distributions, the PRGM predictor of a general linear combination of the finite population values is obtained. Finally, we provide a real-life example to predict a finite population mean and compare the estimated risk and risk bias of the obtained predictors under the LINEX loss function by a simulation study.     

A simple evolutionary model of dormancy and dispersal in heterogeneous patches with special reference to phytophagous lady beetles: I. Stable environments

Summary A simple evolutionary model of dormancy and dispersal is presented with special reference to phytophagous lady beetles. In order to investigate spatially heterogeneous environments, we assume the simplest patch structure, that is, there are only two patches, main and sub. Environments are also assumed to be temporally constant. The main patch is superior to the sub patch, but density effect at the main patch is higher than at the sub patch. Optimal dormancy and dispersal are obtained at the same time by the method of evolutionarily stable strategy (ESS). In the univoltine life cycle, dormancy strategy vanishes because dormant individuals do not reproduce at all but suffer from a certain mortality rate during winter hibernation. In the bivoltine life cycle, the dormancy and dispersal rates constitute a trade-off: the rates change together with a negative correlation when the mortality rate during dispersal or during winter hibernation changes. When suitability of the main patch gradually deteriorates, the optimal strategy changes as follows: neither dormancy nor dispersal is adopted at the most suitable condition, the dispersal rate is increased without dormancy in the intermediate condition, and then the dormancy rate is increased with a constant dispersal rate. We discuss the field observation data of lady beetles in the light of results of our model.     

中国省份创新能力提升了出口韧性吗?——基于中国31个省份的面板数据分析

在国际政治、地缘政治和国际公共安全卫生事件对出口产生冲击的背景下,采取何种政策措施来应对外部冲击、保持出口稳定增长成为政府和企业面临的重要问题。借鉴区域经济韧性的测度方法,基于首次提出的出口韧性测度指标,利用《中国海关进出口统计数据库》测度了1999—2016年中国31个省份(除中国香港、澳门、台湾外)的出口韧性,结合《中国统计年鉴》省份层面的宏观数据,运用固定效应模型,考察了省份创新能力、出口韧性之间的关系和产业内在出口韧性的来源、决定机制。研究发现,省份创新能力的提升有利于提高其出口韧性,省份创新能力对不同地区的省份出口韧性存在异质性影响,在金融危机这一负向外部冲击下,省份创新能力的提升对出口韧性的提高存在显著促进作用。研究表明,要通过深化科技体制改革,加大对新兴产业的税收优惠政策力度,加速出口产业整体向创新驱动发展的转型升级,完善出口产品研发创新链条,促进企业完善人才培养机制等方式来提高省份创新能力,提高出口韧性和稳定出口优势。     

Package Auctions and Exchanges

We report recent advances concerning the package allocation problem, in which traders seek to buy or sell combinations of goods. The problems are most difficult when some goods are not substitutes. In that case, competitive equilibrium typically fail to exist but the core is non‐empty and comprises the competitive solutions. Also in that case, the Vickrey auction fails to select core allocations and yield revenues that are less than competitive. The Ausubel‐Milgrom auction generally selects core allocations and, when goods are substitutes, prescribes the Vickrey allocation. We also evaluate the problems and promise of mechanisms for the package exchange problem.     

有限理性下的社保基金投资监管进化博弈研究

社保基金的投资监管是复杂的决策问题,无法满足主流博弈论“完全理性”的要求。因此从有限理性角度出发,分别建立了基金经理人之间、社保基金管理机构与基金经理人之间的进化博弈模型,求出模型的复制动态方程,研究不同情况下的进化稳定策略,并得到博弈群体的复制动态相位图。     

A note on the Cauchy-type mixture distributions

An interesting class of continuous distributions, called Cauchy-type mixture, with potential applications in modelling erratic phenomena is introduced by Soltani and Tafakori [A class of continuous kernels and Cauchy type heavy tail distributions. Statist Probab Lett. 2013;83:1018–1027]. In this work, we provide more insights into the Cauchy-type mixture distributions, involving certain characterizations, connections with the generalized Linnik distributions and the class of discrete distributions induced by stable laws. We also prove that the Laplace transform of Cauchy-type mixture distributions when normalized by constant terms become as a density functions in terms of distributional conjugate property.     

A note on mixingale limit theorems and stable convergence in law

A gap in the proof of a non stationary mixingale invariance principle is identified and fixed by introducing a skipped subsampling of a partial sum process and letting the skipped interval vanish asymptotically at an appropriate rate as the sample size increases. The corrected proof produces a mixingale limit theorem in the form of a mixing convergence in law, occurring jointly with the stable convergence in law for the same σ-field relative to which they are stable and mixing. The applicability of established results to a high-frequency estimation of the quadratic variation of financial price process is discussed.     

吉林省2000-2005年生育情况分析

吉林省2005年人口出生率7.89‰,低于全国平均水平,人口和计划生育工作形式总体是好的。但通过对吉林省2000-2005年生育情况的调查发现,全省低生育水平面临反弹的现实风险。我们必须清醒地看到,违法生育数量相对增加,一胎违法生育所占比例较大,再婚违法生育占违法多胎生育比例较大。在详细分析产生问题原因的基础上结合工作实际提出解决违法生育增多问题的建议。     

具有正弦、余弦、正切鉴相特性的一类三阶锁相环路方程的定性分析

本文对采用理想积分滤波器和RC积分滤波器得到正弦、余弦、正切鉴相特性三阶锁相环路方程，运用首次近似方法，对等价系统判定平衡点渐近稳定、不稳定及拓扑结构，运用Liapunov函数研究渐近稳定的吸引域，进而提供所论环路方程有失锁点。