建设项目的费用控制以及项目费用管理系统的需求

对于许多项目而言,费用严重超支、交付成果低劣的现象更凸显了需要对项目管理流程进行有效的管理和控制。本文叙述了项目从概念设计阶段到完工整个生命周期的有效费用控制,并介绍了进行这种控制所需要的项目费用管理系统在大型建设项目上的应用。     

Efficiency comparison of M-estimates for scale at t-distributions

Using Fisher's information fort-distributions, the absolute asymptotic efficiency of some M-estimates for scale with known location parameter is calculated and graphically illustrated. The compared estimators are the standard deviationS _*, the mean absolute deviation, called mean deviationD _*, the median absolute deviation, called MAD_*, and some M-estimates for scale, one, which is very robust, and another one with high asymptotic efficiency fort-distributions close to the normal. The last one is considered with monotone (in the positive field) and with very late redescending χ-function too. Also the , an alternative and generalized excess measure defined as the double relative asymptotic variance of the underlying scale estimator in the previous paper, is calculated fort-distributions and graphically illustrated, because there is the relation that the higher the asymptotic efficiency of is, the lower is the corresponding .     

An extension of the ranked set sampling theory

This paper is concerned with ranked set sampling theory which is useful to estimate the population mean when the order of a sample of small size can be found without measurements or with rough methods. Consider n sets of elements each set having size m. All elements of each set are ranked but only one is selected and quantified. The average of the quantified elements is adopted as the estimator. In this paper we introduce the notion of selective probability which is a generalization of a notion from Yanagawa and Shirahata (1976). Uniformly optimal unbiased procedures are found for some (n,m). Furthermore, procedures which are unbiased for all distributions and are good for symmetric distributions are studied for (n,m) which do not allow uniformly optimal unbiased procedures.     

A class of estimators using auxiliary information in sample surveys

A large class of estimators is considered for the mean of a finite population using information on an auxiliary variable. It is shown that members of this class of estimators are asymptotically no more efficient than the linear regression estimator.     

Optimal stabilization policies for housing activity

The usual approach in econometric modeling is to assume that the behavior of government agencies is exogenous. In this paper we have suggested that the policies of government agencies are not truly exogenous and should be studied in relation to the specific objectives pursued by these agencies.Within this framework, we investigated the implications of optimizing the behavior of two U.S. government agencies, Federal Home Loan Bank (FHLB) and Federal National Mortgage Association (FNMA), involved in the housing market. The technique we have utilized is dynamic programming.Based on the assumption that there agencies attempt to stabilize the housing market we have calculated the values for the optimal strategies in the past years and compared them with the historical patterns they have actually followed. Our interpretation of the behavior of these agencies is as follows: FHLB has a significant potential for housing stabilization. However, it has historically put more emphasis on keeping a uniform policy than stabilizing the housing activity. In this way, the role it has played in the housing market may be more destabilizing than stabilizing. On the other hand, FNMA's activity has had a rather uncertain effect on the housing stabilization. The conservative policies that FNMA has followed in the past are consistent with the uncertainties implicit in decision making but, at the same time, can be blamed for failing to create sufficient information regarding their effectiveness on the housing stabilization.     

直辖以来重庆市物质资本存量分产业测算

资本存量是宏观经济分析中不可或缺的基本数据,采用永续盘存法对直辖以来重庆资本存量进行核算.通过计量分析解决了数据缺失问题,在处理了年度数据“变量替代存量”问题基础上,采用相关研究中通用的经验方法确立基准年度资本存量,最后经过价格水平平减处理,给出了直辖以来重庆市三次产业的资本存量数据.对测算结果进行比较分析的结果表明,与相关文献个别年份的总体估计值基本相当,但产业层面略有差异.     

Minimum Scoring Rule Inference

Proper scoring rules are devices for encouraging honest assessment of probability distributions. Just like log‐likelihood, which is a special case, a proper scoring rule can be applied to supply an unbiased estimating equation for any statistical model, and the theory of such equations can be applied to understand the properties of the associated estimator. In this paper, we discuss some novel applications of scoring rules to parametric inference. In particular, we focus on scoring rule test statistics, and we propose suitable adjustments to allow reference to the usual asymptotic chi‐squared distribution. We further explore robustness and interval estimation properties, by both theory and simulations.     

论提高房地产估价师水平的途径

采用综述的方法,从工作的原则性和灵活性、创新意识、政策诠释水平、报告撰写能力、国际观等方面,论述了提高估价师水平的途径;提出了要提高评估质量和评估行业的整体形象,必须提高估价师自身的综合素质,进而促进房地产评估事业健康发展的观点。     

Planning for production in construction: controlling costs in major capital projects

There has been limited research that has examined how the public sector can guarantee their major capital projects are delivered within budget. A Strategic Asset Management Framework (SAMF) developed by the Western Australian State Government, was implemented that ensured their major capital projects were delivered within 5% of their budget. Interviews were conducted with stakeholders who had participated in the delivery of capital projects using the SAMF to understand how it had been used to successfully deliver projects. The interviews highlighted the importance of the SAMF in addressing optimism bias and strategic misrepresentation with the use of independent auditors. The research provides invaluable insights from practice that have been used to control and manage the capital expenditure of assets. Such knowledge is pivotal for ensuring strides are made forward to addressing the cost growth phenomenon that continues to plague major capital projects.     

改进固定工期大中型工程的完工成本估算

传统挣值管理框架内的完工成本估算模型,不能很好适用于工期目标固定的大中型工程。首先,在项目前锋期（t₀）,提出利用进度挣值方法（ES）估算完工工期T₂,以及对于固定工期（T₀）需要压缩的工期（ΔT=T₂-T₀）。然后,采用指数函数模拟时间-费用分阶段凸成本曲线,估算压缩工期的成本。在此基础上,结合Gompertz生长模型（GGM）估算未压缩时的完工成本,提出固定工期大中型工程的完工成本的估算模型。最后,以某机场工程子项目作为案例,分别利用传统挣值法的四种基本估算方法与改进后的挣值管理完工估算方法,对项目完工成本进行估算。横向对比结果发现,改进后的挣值管理完工估算方法具有相对较优性。本研究的成本估算模型改进了传统挣值法对完工成本估算的预测能力,对于进度为主要目标的中国大中型工程具有较强的实践指导意义。