Weighted total least-squares joint adjustment with weight correction factors

Abstract

A joint adjustment involves integrating different types of geodetic datasets, or multiple datasets of the same data type, into a single adjustment. This paper applies the weighted total least-squares (WTLS) principle to joint adjustment problems and proposes an iterative algorithm for WTLS joint (WTLS-J) adjustment with weight correction factors. Weight correction factors are used to rescale the weight matrix of each dataset while using the Helmert variance component estimation (VCE) method to estimate the variance components, since the variance components in the stochastic model are unknown. An affine transformation example is illustrated to verify the practical benefit and the relative computational efficiency of the proposed algorithm. It is shown that the proposed algorithm obtains the same parameter estimates as the Amiri-Simkooei algorithm in our example; however, the proposed algorithm has its own computational advantages, especially when the number of data points is large.     

Conditional Maximum Likelihood and Interval Estimation for Two Weibull Populations under Joint Type-II Progressive Censoring

Comparative lifetime experiments are important when the object of a study is to determine the relative merits of two competing duration of life products. This study considers the interval estimation for two Weibull populations when joint Type-II progressive censoring is implemented. We obtain the conditional maximum likelihood estimators of the two Weibull parameters under this scheme. Moreover, simultaneous approximate confidence region based on the asymptotic normality of the maximum likelihood estimators are also discussed and compared with two Bootstrap confidence regions. We consider the behavior of probability of failure structure with different schemes. A simulation study is performed and an illustrative example is also given.     

Cyclic Polygonal Designs with Block Size 3 and Joint Distance α = 2

Polygonal designs are useful in survey sampling in terms of balanced sampling plans excluding contiguous units (BSECs) and balanced sampling plans excluding adjacent units (BSAs). In this article, the method of cyclic shifts has been used for the construction of cyclic polygonal designs (in terms of BSAs) with block size k = 3 and λ = 1, 2, 3, 4, 6, 12 for joint distance α = 2 and 51 new designs for treatments v ≤ 100 are given.     

Joint Model of Clustered Failure Time Data with Informative Cluster Size

In this article, we propose an estimation procedure to estimate parameters of joint model when there exists a relationship between cluster size and clustered failure times of subunits within a cluster. We use a joint random effect model of clustered failure times and cluster size. To investigate the possible association, two submodels are connected by a common latent variable. The EM algorithm is applied for the estimation of parameters in the models. Simulation studies are performed to assess the finite sample properties of the estimators. Also, sensitivity tests show the influence of the misspecification of random effect distributions. The methods are applied to a lymphatic filariasis study for adult worm nests.     

高校与地方政府共建新型产学研合作平台的探索与实践

加强产学研合作是高校面向经济建设主战场,实现科研成果向现实生产力转化的迫切需求。校地共建产学研合作平台,既是地方产业发展的需要,也是高校提升创新能力的需要,还是市校同发展的体现,对地方政府促进经济建设和社会发展意义重大。     

结果加重犯的共同犯罪问题

共同犯罪的问题一直是刑法理论界研究的重点和难点。结果加重犯是指行为人的一个犯罪行为在已经满足一个基本犯罪的全部构成要件的基础上,又发生了更为严重的结果,因而法律规定加重其刑的犯罪形态。我国刑法关于结果加重犯的共同犯罪问题的理论研究上众说纷纭、莫衷一是。不能成立结果加重犯的共同犯罪并不意味着共犯人对重的结果免责。     

跨国公司对中外合资企业控制关键点的实证研究

有效控制合资企业是跨国公司实现全球战略一体化的要求。但跨国界控制的高成本,东道国政策限制等约束使跨国公司不能实施对合资企业的全面控制。而对跨国合资企业关键点控制的研究多是基于案例分析的结果,既无理论支撑,又无大样本检验,因此缺乏普遍性和说服力。本文在合资企业知识控制理论分析的基础上,提炼出跨国合资企业知识控制的关键点,并通过426家制造业中外合资企业的实证研究证明,跨国公司控制合资企业的关键点是重点控制和计划控制中的六个方面。     

信息技术采用对关系治理的影响:投入专用性的调节效应研究

随着信息技术在供应链中的广泛应用,企业间的竞争合作已成为供应链成员生存和发展的战略选择,供应链合作伙伴关系治理越来越重要,制造商和供应商通过联合行动共同应付投入专用性等带来的问题,从而促进双方的合作。文章在分析和总结前人研究成果基础上,重点探讨信息技术采用对企业间关系治理的影响,以及在企业信息化过程中投入专用性和信任的调节作用,并运用来自海峡西岸经济区制造商和供应商的调研数据,利用基于调节效应的结构方程模型进行实证研究表明,在联合行动过程中,信任的调节作用显著,在事前的联合计划阶段,投入专用性的调节作用显著,而在后期的联合解决问题阶段,投入专用性的调节作用并不显著,为企业在信息系统采用过程中处理各种资产的专用性投入提供一些理论上的借鉴和实践上的启示。     

共有产权保障性住房制度中的法律问题及公证应对

共有产权保障性住房作为未来保障性住房的主要模式,已经基本得到法律法规的确认,但现阶段立法者的精力主要集中于宏观架构,忽略了制度运行中的具体问题。在购房未满5年的期限内转让、担保、出租甚至分割应有份额的约定属于违法行为,公证机关应拒绝办理此类公证;因房屋使用、管理产生的债务可完全由受保障对象承担,由于不具有公示效力,政府并不因此而免责,公证机关应谨慎审核该类约定条款;因房屋侵权所产生的债务可完全由受保障对象承担,公证机关可对此予以公证;物业费、业主权等事宜可完全由受保障对象承担、享有,公证机关可对此办理公证;一般管理行为可明定受保障对象单独为之,重大修缮行为则不宜使政府的决策权被多数决机制架空,公证机关需进行实质审查;不论法定继承,还是遗嘱继承,公证机关均需谨慎对待5年禁售期内的继承公证,对超过5年禁售期的相关继承公证则可持相对宽松态度。     

混业趋势下中国金融控股公司发展研究

随着经济全球化和金融一体化进程的加快,全球金融由分业经营向混业经营发展的趋势日益明显,金融控股公司作为混业经营的模式之一,成为许多金融机构积极推进的目标.金融控股公司在国外已经有较长时间的历史,但在我国还算是新生事物,在已经加入世界贸易组织5年的形势下,加强对金融控股公司的研究,对于规范我国现有的金融控股公司,增强金融业的国际竞争力,防范和化解金融风险,具有十分重要的现实意义.