The conduct of the sample average when the first moment is infinite

Summary Many books about probability and statistics only mention the weak and the strong law of large numbers for samples from distributions with finite expectation. However, these laws also hold for distributions with infinite expectation and then the sample average has to go to infinity with increasing sample size. Being curious about the way in which this would happen, we simulated increasing samples (up to n= 40000) from three distributions with infinite expectation. The results were somewhat surprising at first sight, but understandable after some thought. Most statisticians, when asked, seem to expect a gradual increase of the average with the size of the sample. So did we. In general, however, this proves to be wrong and for different parent distributions different types of conduct appear from this experiment. The samples from the “absolute Cauchy”-distribution are most interesting from a practical point of view: the average takes a high jump from time to time and decreases in between. In practice it might well happen, that the observations causing the jumps would be discarded as outlying observations.     

The conduct of the sample average when the first moment is infinite

Summary  Many books about probability and statistics only mention the weak and the strong law of large numbers for samples from distributions with finite expectation. However, these laws also hold for distributions with infinite expectation and then the sample average has to go to infinity with increasing sample size.
Being curious about the way in which this would happen, we simulated increasing samples (up to n = 40000) from three distributions with infinite expectation. The results were somewhat surprising at first sight, but understandable after some thought. Most statisticians, when asked, seem to expect a gradual increase of the average with the size of the sample. So did we. In general, however, this proves to be wrong and for different parent distributions different types of conduct appear from this experiment.
The samples from the "absolute Cauchy"-distribution are most interesting from a practical point of view: the average takes a high jump from time to time and decreases in between. In practice it might well happen, that the observations causing the jumps would be discarded as outlying observations.     

A less sensitive linear detector for the change point based on kernel smoothing method

In this paper, a new detecting procedure for the change point in the mean is proposed based on a linear kernel smoother. It uses a discontinuous kernel function and has a relative high constant efficiency in an interval of shift value and thus is less sensitive than the simple CUSUM, EWMA, FMA and Shiryayev-Roberts procedures. It also generalizes the FMA procedure.     

基于顾客价值的顾客心理契约研究——以电信市场为例

激烈的竞争环境下,企业要获得一席之地,必须给顾客提供高让渡价值,使顾客形成情感依赖达到忠诚。当然,不管是交易型价值还是关系型价值,都是顾客通过与自己预期值的比较而得到的一种感受,是交换中的顾客依据个人主观判断完成的,可见顾客价值和顾客心理契约是对应的。     

中国公司治理法律制度的形成和价值取向

在有关中国公司治理应当是什么样这种公司治理的“应当”的问题上,很多学者提出了很多看法。公司治理可以分为重视股东利益的股东主权型公司治理模式和重视职工等利益相关者利益的利益相关者公司治理模式,因此,学者们提出的看法也可以概括到这两种模式中。总体来看,2005年《公司法》的价值取向是保护中小股东。但是对公司治理的形成来讲,社会规范或者社会对公司的角色期待以及公司自身的认知等因素是重要的,应该从中国社会的对公司的角色期待如何或者中国社会责任应当如何的角度出发分析公司治理制度的趋向。从和谐社会的建设的社会目标来看,中国的公司治理发展方向应该是利益相关者主权型模式,尤其是侧重于职工的模式,而不是股东主权型公司治理模式。     

Ecological tax reform—a value chain level approach

This study assesses the effects of an ecological tax reform on three value chains. These case studies lead to an analysis of the business strategy options when companies face a shift in the relative prices of their production factors. The results support earlier research findings that the direct effects of an ecological tax reform on the price competitiveness of companies is on average rather small. However, the effects of the reform are shown to vary significantly between the different parts of the value chain. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment     

Career lesbians. Getting hired for not having kids?

Using a field experiment, we investigate whether discrimination based on women's sexual orientation differs by age and family constraints. We find weakly significant evidence of discrimination against young heterosexual women. This effect is driven by age (and fertility) rather than by motherhood. We do not find any unequal treatment at older ages. This age effect is consistent with our theoretical expectation that, relative to lesbian women, young heterosexual women are penalised for getting children more frequently and taking on, on average, more at‐home‐caring tasks.     

A dymimic model of housing price determination

This paper presents and estimates a model of the resale housing market. The data are a cross-section of monthly time series obtained from the multiple-listing service for a suburb of San Diego. The model is specified and estimated as a dynamic multiple indicator multiple cause system of equations where the capitalization rate is taken to be an unobservable time series to be estimated jointly with the unknown parameters. These are estimated by maximum likelihood using an EM algorithm based upon Kalman filtering and smoothing.The specification of the model features hedonic equations for each house sale and a dynamic equation for the capitalization rate which is constrained to make the expectation of prices equal the present value of the net returns to home ownership whenever the economic variables stabilize at steady state values. Out of steady state, the capitalization rate slowly adapts to new information.The model attributes a large portion of housing price increases of the 1970's to a fall in the capitalization rate which in turn was driven by rental inflation, tax rates and mortgage rates. Post-sample simulations indicate an initial flattening of housing inflation rates and later a fall brought on by the increase in steady state capitalization rates. In-sample simulations show that although both Proposition 13 and the inflation induced rise in the marginal income tax rates provided partial explanations for the fall in capitalization rates, the single most important factor was the acceleration in price of housing services which interacted with the tax treatment of home ownership to produce an amazing 18% average annual rate of price increase over the last seven years of the 1970's.     

Performance compensation contracts and CEOs’ incentive to shift risk to debtholders: An empirical analysis

The paper investigates the relationships among CEO incentive contracts, manager ownership, charter value, and bank risk taking. We analyze whether the presence and magnitude of incentive contracts induce CEOs of financially distressed firms and firms with high manager ownership to take unprofitable risks that shift wealth from debtholders to equity holders. Our sample focuses on banks that had both the incentive and opportunity to shift risks, and compares them with those that did not. We compare weak and strong banks in periods when the banks’ principal creditor, the FDIC, was a lenient and then a stringent monitor. The evidence is consistent with bonus compensation inducing CEOs of financially weak firms to shift risk to debtholders only if they do not have large insider ownership. The evidence is also consistent with these contracts rewarding CEOs for their effort to manage unforeseeable risk albeit not their ability. Low charter value banks with high managerial ownership took profitable risk during the lenient regulatory period.     

信息、信号偏差与价格行为

从报价者和交易者的决策最优化行为出发,考虑到信息以及报价者和交易者的预期信号偏差对价值的随机影响,模型化证券市场价格的形成。信息对资产价值的影响可表示为一个复合泊松过程。这样的信息过程导致价格分布表现出尖峰、胖尾的特征,产生的价格序列是非平稳的、自相关的。同时,在价格形成的过程中,人们对信息的预期信号偏差也影响市场价格。价格形成的信息模型启示我们应加强市场信息—预期—价格机制的建设。     

信用模型与信用机制研究

信用缺失是我国社会经济中的一个严重问题。通过对交易过程中的信用博弈分析,建立了信用模型。认为交易活动中的信用既与理性主体的期望价值(V)有关,又与理性主体对其他参与人的信任度(P)有关。运用信用模型对信用机制的两种作用方式进行了研究,指出抑制信用缺失要首先注重信用文化建设,在此基础上完善信用法治。     

A panel data approach to economic forecasting: The bias-corrected average forecast

In this paper, we propose a novel approach to econometric forecasting of stationary and ergodic time series within a panel-data framework. Our key element is to employ the (feasible) bias-corrected average forecast. Using panel-data sequential asymptotics we show that it is potentially superior to other techniques in several contexts. In particular, it is asymptotically equivalent to the conditional expectation, i.e., has an optimal limiting mean-squared error. We also develop a zero-mean test for the average bias and discuss the forecast-combination puzzle in small and large samples. Monte-Carlo simulations are conducted to evaluate the performance of the feasible bias-corrected average forecast in finite samples. An empirical exercise, based upon data from a well known survey is also presented. Overall, these results show promise for the feasible bias-corrected average forecast.     

商业银行信用风险控制在助学贷款中的运用

实行助学贷款是发展教育的一项重要政策,但在实施的过程中却出现了"银行有钱贷不出"和"学生没钱贷不到"的尴尬局面,这引起了人们对这项政策的再思考。通过对产生这种现象的内在原因的分析和对银行和学生二者之间预期效用的比较分析,以及对银行和学生行为选择的分析,认为缺乏有效的抵押担保机制和良好的社会信用体系是导致这种现象的重要原因,最后从制度约束和道德约束两方面思考,减少信息不对称现象,增加学生不还贷成本,降低银行风险,不断完善助学贷款制度。     

预期对我国住房市场政策调控效果影响的实证分析

预期对房地产行业调控政策的实施效果有着重要的作用。一般来说,从形成机制可以把预期分为静态预期、外推型预期、适应性预期和理性预期,而我国的房地产市场因其特殊性,是介于适应性预期与理性预期之间的准理性预期。通过建立住房价格调控模型并进行实证分析后,可以发现准理性预期是一种效果较好且与实际更相符的预期;预期是影响房价的最主要因素,而预期对于房价的放大效应和预期的不稳定性又使得政策调控增加了一定的难度;房价基本上与预期成正比关系。     

The asymmetry of judgemental confidence intervals in time series forecasting

In forecasting a time series, one may be asked to communicate the likely distribution of the future actual value, often expressed as a confidence interval. Whilst the accuracy (calibration) of these intervals has dominated most studies to date, this paper is concerned with other possible characteristics of the intervals. It reports a study in which the prevalence and determinants of the symmetry of judgemental confidence intervals in time series forecasting was examined. Most prior work has assumed that this interval is symmetrically placed around the forecast. However, this study shows that people generally estimate asymmetric confidence intervals where the forecast is not the midpoint of the estimated interval. Many of these intervals are grossly asymmetric. Results indicate that the placement of the forecast in relation to the last actual value of a time series is a major determinant of the direction and size of the asymmetry.     

Power shifts in organizations: the role of high-performance work systems

This paper analyses the effects of high-performance work systems (HPWS) on the rent appropriation of employees and shareholders in firms from the viewpoint of appropriation theory. Applying a meta-analytical approach I test the hypothesis that HPWS shift the balance of power between stakeholder groups in an organization, favouring employees over other stakeholders. This hypothesis is confirmed. However, the overall results of HPWS are positive for both stakeholder groups, as HPWS also increase firm value creation. My study also emphasizes the need to decompose the construct ‘firm performance’ into value creation and value distribution among stakeholder groups. Directions for future research and recommendations for management practice conclude the paper.     

基于交易者预期的房地产价格变化模型

本文基于交易者预期和正反馈,建立了一个房地产价格变动模型.根据该模型,分类讨论了交易者对房地产政策预期的不同,对房地产价格演变方向的影响.研究结果表明,房地产调控政策能否有效,除取决于政策出台时间、政策力度外,还取决于其能否有效改变交易者对市场未来走势的预期.     

基于供应链一体化的CRM模式研究

由于外部环境和自身资源的限制，单个企业在进行CRM时往往在信息和信任方面出现问题而使CRM达不到预期目标．以供应链一体化为基础的CRM不是在单个企业和顾客之间建立互动关系，而是以关键顾客和合适顾客的需要为起点，以顾客需求满足过程中的价值最大化为目标的全方位全流程的互动活动。     

An analysis of university year-round operation

The implementation of year-round operation has often been suggested as a means for accommodating additional demand for student admissions at a university campus of fixed capacity. However, because the student flow process at a university has not been well understood, many institutions have been disappointed to find the actual benefits resulting from the addition of a regular summer program of instruction to be far less than they had expected. This paper demonstrates that, due to established patterns of student attendance, a reasonable expectation of a change to year-round operation is that the undergraduate admission rate will increase by 5 per cent when enrollment is held fixed. Moreover, the summer term will attract only one-third as many undergraduate students as are enrolled during the regular academic year. These computations assume that no attempt is made to exert control over student attendance patterns.A queueing model is developed that relates the admission rate to the proportion of students who belong to various cohorts with common workload requirements and attendance patterns. Data gathered at the University of California, Berkeley campus is used to estimate these proportions for a campus which offers a year-round program. From these estimates are derived values for the overall admission rate and the ratio of summer enrollment to average nonsummer enrollment. These values are then compared with those obtained for a campus of like size which does not offer a year-round program of instruction. The paper concludes that, unless an institution is willing to exert control over student attendance patterns, university year-round operation is probably not economical in a society which places heavy emphasis on the summer as a time when students should vacation or take temporary jobs.     

Determinants of Relative Sectoral Prices: The Role of Demographic Change

Demographic change raises demand for non‐tradable old‐age related services relative to tradable commodities. This demand shift increases the relative price of non‐tradables and thereby causes real exchange rates to appreciate. We claim that the change in demand affects prices via imperfect intersectoral factor mobility. Using a sample of 15 OECD countries, we estimate a robust increase of relative prices. According to our main estimate, up to one fifth of the average increase in relative prices between 1970 and 2009 can be attributed to population ageing. Further findings confirm the relevance of imperfect factor mobility: Countries with more rigid labour markets experience stronger price effects.