Housing tenure choice and the dual income household

Housing tenure choice has been the subject of a very large literature. Many treatments have sought to estimate the effect of household income on the likelihood of home ownership. To date, no study has ever disaggregated the household income of married couples into the separate labor income components to see if one partner’s income has a different effect than the other. Using a derived likelihood function to control for censoring in the wife’s income, this paper estimates the effect of separate incomes on housing tenure choice, accounting for possible endogeneity of the wife’s income. To compare the results of this estimation method, the paper also estimates the standard IV models, 2SLS and IV probit. While the results show that there is no endogeneity of the wife’s income, ignoring the censoring of the endogenous variable (when a large fraction of observations are censored) can possibly lead to biased coefficient estimates. Also, this paper confirms the importance of total household income, which has a larger effect than the total disaggregated components.     

Optimal and efficient repeated measurements designs for comparing test treatments with a control

Rearranging the sequence of test treatments and control treatment within each block of an A-optimal balanced treatment block design such that certain conditions are satisfied, the resulting design is an A-optimal repeated measurements designs when blocks are regarded as units or periods. The efficiencies of designs which are obtained from universally optimal repeated measurements designs with test treatments only by changing some treatment labels into control treatment are given.     

Versuchsanordnungen in unvollständigen Blöcken mit zusätzlichen Kontrollbehandlungen in jedem Block

Summary The analysis of the usual balanced incomplete block designs is extended to the case where, in addition to the experimental treatments, one or several control treatments are contained in each block.      

Comparing means of several treatments with a control when one observation exists per treatment

In an one-way analysis of variance with standard assumptions suppose that only one observation exists per treatment. In addition, assume that one of the treatments is a control group. Because of insufficient observations, the variance of the populations cannot be estimated and hence the usual methods for comparing treatments with the control group fail. In this paper, we present a method to compare treatments with a control when one observation exits per treatment. An algorithm is given to estimate the critical values of the test. The power of the test is investigated by a Monte Carlo simulation; numerical studies show that when there is a treatment whose mean is close to the control group, the power of the test is satisfactory.     

Control Function Approach for Partly Ordered Endogenous Treatments: Military Rank Premium in Wage

In treatment effect analysis, there are many cases where the treatment of interest is ordered (e.g. general‐education years or medicine doses) and the control treatment is not zero, but a different type of treatment (a vocational training or a surgery). We develop an approach to find effects of partly ordered treatments, while correcting for possible treatment endogeneity with nearly parametric control functions. We use this control function approach, along with its supplementary version, to estimate effects of military ranks (ordered treatments) on wage relative to non‐veteran status (control treatment) with the Wisconsin Longitudinal Study data. In our empirical analysis, the military rank effects differ much: officer has large positive effects, but enlisted ranks have small or no effects.     

物流控制策略的关键--产品分类管理

当今时代，产品种类越来越多，生命周期越来越短，利润越来越薄。如何对产品物流进行控制，以支持销售，降低库存成本，关键在于对产品进行分类，实现分类管理，本文详细探讨对产品如何进行分类。     

Optimal Allocation for Comparing <Emphasis Type="Italic">k</Emphasis> Test Treatments to Positive and Negative Control with Unequal Weighting Under A-optimality and MV-optimality

Experiments in real life often involve comparisons of test treatments to more than one control. However, the controls may not always be of equal importance. In this paper we introduce weighted MV optimality criterion and present a detailed study using both weighted A and MV optimality criteria, of the problem of optimally comparing a set of test treatments to two controls (positive and a negative) that are of unequal importance to the experimenter.     

Treatment and Control Groups in a Dynamic Setting

The paper considers a version of the question of how to define treatment and control groups in a dynamic setting where treatments can occur at any time (but only once). The version considered pre‐supposes that treatments as well as outcomes can be conceptualised as events occurring in temporal locations of a discrete time axis. It is proposed to think of effects as being dependent on both the time when and the time since the treatment occurred. The paper develops corresponding definitions of treatment and control groups, and proposes a notion of ‘comprehensive treatment effect’ that takes into account how treatment and control groups are generated. Based on this notion, the paper discusses causal interpretations that do not pre‐suppose a potential outcomes framework.     

Efficient venture capital financing combining debt and equity

I present a model of venture capital contracting in which contracts that involve a mixture of both debt and equity are efficient and dominate pure-equity and pure-debt financing. The optimal contract balances the venture capitalist's incentive to intervene in the project and the entrepreneur's desire for control. Received: 9 September 1997 / Accepted: 3 April 1998     

Linear rank tests for comparing treatments with a control when data are subject to unequal patterns of censorship

A class of asymptotically distribution-free tests is considered for comparing several treatments with a control when the, data are subject to unequal right-censorship. A particular member of this class is proposed for use in practice and an illustrative numerical example is given. A general result for the Pitman efficacy of a test based on an asymptotically normal test statistic is proved for the multiparameter case and using this result the efficacy of the proposed class of tests is obtained under sequences of translation and proportional hazards alternatives. Simulation studies are conducted to compare the performance of the proposed test, in terms of power, with some other tests.     

谈建设单位对工程变更的有效控制和管理

工程变更往往涉及费用和工期的变化,影响工程目标的控制,甚至引起争议或索赔。文章就建设单位如何控制和管理工程变更谈点个人体会。     

试论矿井安全供电

矿井供电必须保证安全、可靠、经济,且有良好的供电质量和供电能力。该文从供电的基本要求入手,根据煤矿生产的环境特点,结合现场实际,阐明了安全供电的重要性,并提出相应的防治对策。     

Identification Based on Difference‐in‐Differences Approaches with Multiple Treatments

This paper discusses identification based on difference‐in‐differences (DiD) approaches with multiple treatments. It shows that an appropriate adaptation of the common trend assumption underlying the DiD strategy for the comparison of two treatments restricts the possibility of effect heterogeneity for at least one of the treatments. The required assumption of effect homogeneity is likely to be violated because of non‐random assignment to treatment based on both observables and unobservables. However, this paper shows that, under certain conditions, the DiD estimate comparing two treatments identifies a lower bound in absolute values on the average treatment effect on the treated compared to the unobserved non‐treatment state, even if effect homogeneity is violated. This is possible if the treatments have ordered treatment effects, that is, in expectation, the effects of both treatments compared to no treatment have the same sign, and one treatment has a stronger effect than the other treatment on the respective recipients. Such assumptions are plausible if treatments are ordered or vary in intensity.     

违章行为分类和研究

针对煤矿安全生产中矿工违章行为问题,在参考现有有关违章行为分类的基础上,重新对违章行为进行分类,然后针对矿工违章行为提出了采取"意识——学习——环境"相结合的矿工自主安全管理模式,以期为有效控制矿工违章行为、促进煤矿安全生产提供借鉴。     

Multiproject team assignments

We consider expected profit maximizing mechanisms for a principal who has to allocate a group of agents among a number of projects, assuming that the principal has incomplete information about each agent's ability type, and the agents follow the Bayes-Nash or the dominant strategy equilibrium behavior. We find that while expected profit maximizing mechanisms are similar to the optimal auction (Myerson, 1981), the incentive compatibility constraints are much more restrictive. Interestingly, these constraints are satisfied if each agent's characteristics change in a consistent manner not only with types, but also from project to project. Received: 30 April 1997 / Accepted: 22 December 1998     

公司库存优化方法浅析

库存是企业生产管理的重点内容之一,库存管理所要解决的核心问题是如何保证在不断提升客户服务满意度的前提下将库存成本控制在最低的范围之内。每个企业应当根据自身的现实条件和市场环境来确定最适合本企业的库存管理方案。N公司想要保持一个较低的库存水平,首先需要对库存材料进行分类．得出真正需要重点关注的物料清单,运用合适的采购订货策略．力求达到在按时满足客户需求的前提下使库存成本最低．．     

A企业的供应商分类策略研究

在整个物资采购网络中，为了增强对供应商管理和控制的有效性，企业应将供应商划分为不同类型的群体。然后对不同类型的物资供应商采取不同的供应商管理模式．以节省管理成本，提高采购柔性，适应市场的变化。从企业供应商分类的现状及存在的问题着手．以物品本身的重要性和其供应市场复杂程度为依据，重新建立采购物品分类模型，最后通过企业实例进行了验证分析。     

Organizational restructuring in response to changes in information-processing technology

This paper examines the effects of changes in information-processing technology on the efficient organizational forms of data-processing in decision-making systems. Data-processing is modelled in the framework of the dynamic parallel processing model of associative computation with an endogenous set-up costs of the processors. In such a model, the conditions for efficient organization of information-processing are defined and the architecture of the efficient structures is considered. It is shown that decreasing returns to scale of the function describing data- processing technology and the information overload of the system are necessary and sufficient conditions for the hierarchical information- processing, respectively. Moreover, the size of the efficient structures is determined exclusively by their information workload and the current state of information-processing technology. Received: 5 June 1996 / Accepted: 17 June 1999     

International Standardisation and Harmonisation: a New Measurement Technique

We argue in this paper that it is the availability of alternative accounting treatments and the use by individual firms of the appropriate method that produces financial statements which are comparable. Accordingly, international harmony in accounting should be seen as a state in which firms throughout the world are able to use an internationally-recognised accounting treatment that is appropriate to their circumstances without being constrained to do otherwise by local accounting regulations or other requirements to adopt practices confined to particular nations. The paper distinguishes harmonisation from standardisation and presents a method for measuring harmonisation which allows for choice between alternative accounting treatments. The statistical model also takes account of the stylised fact that accounting treatments are not mutually exclusive, and the method is illustrated by an analysis of goodwill accounting practices in Europe.