劳动收入份额的决定与波动机制研究

本文通过数理经济模型的理论分析和计量经济模型的实证分析发现,决定社会产品初次分配中劳动收入份额高低的因素,除了政府的生产税税率之外,主要是劳动者的实际工资水平和生产技术水平,且二者的作用方向完全相反,都取决于要素替代弹性的大小。当资本和劳动的替代弹性小于1时,劳动者的实际工资水平越高,劳动收入份额就越高,劳动者的生产技术水平越高,劳动收入份额就越低;而当资本和劳动的替代弹性大于1时,则劳动者的实际工资水平越高,劳动收入份额就越低;劳动者的生产技术水平越高,劳动收入份额就越高。理论和实证的分析还表明,劳动者货币工资水平和实际工资水平的增长随着经济周期的波动而波动,实际工资水平增长率的波动与经济周期的波动方向相反,导致劳动收入份额也随经济周期反向波动。     

Locally best invariant test for outliers in a gamma type distribution

It is shown that the locally best invariant test for the existence of outliers for scale parameters of the gamma distribution is given by Bartholomew's test for exponentiality which is the ratio of the sum of squares of the data to the square of the sample mean. The optimality robustness, including null and nonnull robustness of the test is shown. A small simulation study to compare the power among the other eight competitive tests for testing exponentiality is performed. It is seen that the locally best invariant test is not always best but is reasonably good. It is slightly better than Cochran's test and suffers less from the limiting masking effect.     

Some practical advice on polynomial regression analysis from blocked response surface designs

It is often necessary to run response surface designs in blocks. In this paper the analysis of data from such experiments, using polynomial regression models, is discussed. The definition and estimation of pure error in blocked designs are considered. It is recommended that pure error is estimated by assuming additive block and treatment effects, as this is more consistent with designs without blocking. The recovery of inter-block information using REML analysis is discussed, although it is shown that it has very little impact if the design is nearly orthogonally blocked. Finally prediction from blocked designs is considered and it is shown that prediction of many quantities of interest is much simpler than prediction of the response itself.     

Category Distinguishability and Observer Agreement

It is common in the medical, biological, and social sciences for the categories into which an object is classified not to have a fully objective definition. Theoretically speaking the categories are therefore not completely distinguishable. The practical extent of their distinguishability can be measured when two expert observers classify the same sample of objects. It is shown, under reasonable assumptions, that the matrix of joint classification probabilities is quasi-symmetric, and that the symmetric matrix component is non-negative definite. The degree of distinguishability between two categories is defined and is used to give a measure of overall category distinguishability. It is argued that the kappa measure of observer agreement is unsatisfactory as a measure of overall category distinguishability.     

A simple and asymptotically optimal test for the equality of k(≥2) exponential distributions based on type II censored samples

A test for the equality of two or more two-parameter exponential distributions is suggested. It is developed on an intuitive basis and is obtained by combining two independent tests by the Fisher method (1950, pp. 99-101). The test is simple for application and is optimal asymptotically in the sense of Bahadur efficiency (1960). A numerical example is discussed to illustrate its application in a real-world situation. The Monte Carlo simulation is used for calculating its power which is compared with that of the test suggested by Singh and Narayan (1983). The suggested test is found oftener more powerful.     

SEMIPARAMETRIC ESTIMATION OF THE ERROR DISTRIBUTION IN MULTIVARIATE REGRESSION USING COPULAS

A semiparametric method is developed to estimate the dependence parameter and the joint distribution of the error term in the multivariate linear regression model. The nonparametric part of the method treats the marginal distributions of the error term as unknown, and estimates them using suitable empirical distribution functions. Then the dependence parameter is estimated by either maximizing a pseudolikelihood or solving an estimating equation. It is shown that this estimator is asymptotically normal, and a consistent estimator of its large sample variance is given. A simulation study shows that the proposed semiparametric method is better than the parametric ones available when the error distribution is unknown, which is almost always the case in practice. It turns out that there is no loss of asymptotic efficiency as a result of the estimation of regression parameters. An empirical example on portfolio management is used to illustrate the method.     

不完全信息下纯交换帕累托最优的实现研究

现有的理论中，纯交换帕累托最优状况不是唯一的，且认为只要进行交换就必然能实现帕累托最优。其原因是纯交换帕累托最优条件不充分和交换原则存有缺陷。根据交换是一个讨价还价的过程，采用博弈分析方法，在不完全信息条件下，只要遵循理性人交换原则，交换必能实现，但不一定是帕累托最优。如果信息不对称方所判断的效用函数没有改变对方真实效用函数的偏好性质，交换必然能达到唯一的帕累托最优状况，但利益分割不公平，存在交换剥削；如果效用函数的偏好性质改变，帕累托最优不能实现，而是帕累托改进，但其消费状态也是唯一的。     

对生产帕累托最优条件充分性的质疑与改进

现有的理论中,生产帕累托最优条件不充分,其最优状态不是唯一的,使得理论自身及随后的应用上产生了一些矛盾。确定唯一最优状态的充分条件应该是：双方都满意的交换利益分割和边际技术替代率相等。前者保证交换实现,后者保证交换产生的利益被完全穷尽。只要遵循新交换原则,交换必能实现,但不一定是帕累托最优。信息不充分时,如果信息不对称者对对方所判断的生产函数改变了其真实生产函数的技术性质,交换虽能实现,但生产并没有达到帕累托最优。     

Optimum reliability acceptance sampling plans under progressive type-I interval censoring with random removal using a cost model

A reliability acceptance sampling plan (RASP) is a variable sampling plan, which is used for lot sentencing based on the lifetime of the product under consideration. If a good lot is rejected then there is a loss of sales, whereas if a bad lot is accepted then the post sale cost increases and the brand image of the product is affected. Since cost is an important decision-making factor, adopting an economically optimal RASP is indispensable. This work considers the determination of an asymptotically optimum RASP under progressive type-I interval censoring scheme with random removal (PICR-I). We formulate a decision model for lot sentencing and a cost function is proposed that quantifies the losses. The cost function includes the cost of conducting the life test and warranty cost when the lot is accepted, and the cost of batch disposition when it is rejected. The asymptotically optimal RASP is obtained by minimizing the Bayes risk in a set of decision rules based on the maximum likelihood estimator of the mean lifetime of the items in the lot. For numerical illustration, we consider that lifetimes follow exponential or Weibull distributions.     

通货膨胀预期、企业成长性与企业投资

本文实证检验了通货膨胀预期对企业投资行为的影响及其内部机理来分析通货膨胀预期变化的经济后果。研究发现,宏观预期通货膨胀率的上升会促使微观企业增加当期资本支出规模,但是降低投资效率。进一步分析结果表明：第一,预期通货膨胀率越高,高成长性企业的投资水平显著提高,投资效率显著下降,这一结果在低成长性企业中并不显著;第二,宏观预期通货膨胀率升高,银行更愿意借款给企业。这一结果在高成长性企业中同样显著,在低成长性企业中并不显著。这说明通货膨胀预期通过外部融资促使公司投资,高成长性企业比低成长性企业能够获得更多的银行贷款,从而增加资本投资,而低成长性企业受通货膨胀预期的影响被弱化。     

Non-minimaxity of linear combinations of restricted location estimators and related problems

The estimation of a linear combination of several restricted location parameters is addressed from a decision-theoretic point of view. Although the corresponding linear combination of the unbiased estimators is minimax under the restricted problem, it has a drawback of taking values outside the restricted parameter space. Thus, it is reasonable to use the linear combination of the restricted estimators such as maximum likelihood or truncated estimators. In this paper, a necessary and sufficient condition for such restricted estimators to be minimax is derived, and it is shown that the restricted estimators are not minimax when the number of the location parameters is large. The condition for minimaxity is examined for some specific distributions. Finally, similar problems of estimating the product and sum of the restricted scale parameters are studied, and it is shown that analogous non-dominance properties appear when the number of the scale parameters is large.     

A statistical test for the hypothesis of Gaussian random function

A Gaussian random function is a functional version of the normal distribution. This paper proposes a statistical hypothesis test to test whether or not a random function is a Gaussian random function. A parameter that is equal to 0 under Gaussian random function is considered, and its unbiased estimator is given. The asymptotic distribution of the estimator is studied, which is used for constructing a test statistic and discussing its asymptotic power. The performance of the proposed test is investigated through several numerical simulations. An illustrative example is also presented.     

递归均值调整单位根检验能提高检验功效吗?

根据备择假设成立时均值是否为零,讨论了三类单位根检验统计量的检验功效。理论研究表明:在大样本下,检验功效只与检验类型有关,与均值取值无关。蒙特卡洛模拟表明:在有限样本下,均值会影响检验功效,当均值为零时,第一类DF检验功效最高;当均值大于零时,在绝大多数场合下,第二类DF检验功效最优。因此,递归均值调整单位根检验功效仅在有限条件下最大。     

On robustness of usual confidence region under transformation misspecification

Robustness of confidence region for linear model parameters following a misspecified transformation of dependent variable is studied. It is shown that when error standard deviation is moderate to large the usual confidence region is robust against transformation misspecification. When error standard deviation is small the usual confidence region could be very conservative for structured models and slightly liberal for unstructured models. However, the conservativeness in structured case can be controlled if the transformation is selected with the help of data rather than prior information since this is the case when data is able to provide a very accurate estimate of transformation.     

Sequential search using question-sets with bounded intersections

The paper is concerned with sequential search on a finite set: an unknown element of the finite set is to be found testing its subsets, and getting the information that the unknown element is or is not an element of the tested subset. The optimum of the strategy lengths is found under the condition that the intersection of any two different test-sets is bounded. This condition is generalized taking the intersection of any m different test-sets instead of two, and the general problem is also solved.     

A note on Stein-type shrinkage estimator in partial linear models

In this paper, an exact sufficient condition for the dominance of the Stein-type shrinkage estimator over the usual unbiased estimator in a partial linear model is exhibited. Comparison result is then done under the balanced loss function. It is assumed that the vector of disturbances is typically distributed according to the law belonging to the sub-class of elliptically contoured models. It is also shown that the dominance condition is robust. Furthermore, a nonparametric estimation after estimation of the linear part is added for detecting the efficiency of the obtained results.     

A statistical measure of internal consistency

A test for homogeneity of several populations against the simple tree alternative is proposed when the observations in various groups are subject to the same pattern of random right-censorship. The test is a generalization of the one proposed by Slivka (1970) which is useful when testing time is expensive so that an early termination of an experiment is desirable. The power of the test is examined in a simulation study.     

A Modified Knox Test of Space-Time Clustering

Tests of space-time clustering such as the Knox test are used by epidemiologists in the preliminary analysis of datasets where an infectious aetiology is suspected. The Knox test statistic is the number of cases close in both space and time to another case. The test statistic proposed here is the excess number of such cases over that expected under H₀ of no infection. It is argued that this modified test is more powerful than the Knox test, because the test statistic is not heavily tied as is the Knox test statistic. The use of the test is illustrated with examples.     

Book Reviews

This article uses a Bayesian unit-root test in stochastic volatility models. The time series of interest is the volatility that is unobservable. The unit-root testing is based on the posterior odds ratio, which is approximated by Markov-chain Monte Carlo methods. Simulations show that the testing procedure is efficient for moderate sample size. The unit-root hypothesis is rejected in seven market indexes, and some evidence of nonstationarity is observed in the TWSI of Taiwan.     

Testing the equality among distribution functions from independent and right censored samples via Cramér–von Mises criterion

The traditional Cramér–von Mises criterion is used in order to develop a test to compare the equality of the underlying lifetime distributions in the presence of independent censoring times. Its asymptotic distribution is proved and a resampling plan, which is valid for unbalanced data situations, is proposed. Its statistical power is studied and compared with commonly used linear rank tests by Monte Carlo simulations and a real data analysis is also considered. It is observed that the new test is clearly more powerful than the traditional ones when there exists no uniform dominance among involved distributions and in the presence of late differences. Its statistical power is also good in the other considered scenarios.