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1.
Qualitative response models (QRM's) are analyzed from the Bayesian point of view, using diffuse and informative prior distributions. Exact finite-sample Bayesian and large-sample Bayesian and non-Bayesian estimation results are compared. In addition, the paper provides: (1) plots and discussion of the properties of likelihood functions for QRM's, (2) posterior distributions for logit models' derivatives and elasticities, (3) Bayesian prediction procedures for QRM's, (4) new estimates for the median and other fractiles of the logistic distribution, (5) posterior odds ratios for model selection problems, and (6) comparisons of two alternative Monte Carlo numerical integration procedures. It is concluded that asymptotic approximations are not accurate for small-to moderate-sized samples even when only a single input variable is used, and that operational Bayesian methods are available for providing both exact small-sample and large-sample approximate inferences for DRM's.  相似文献   

2.
The optimal number of levels is studied for the one-way random model with normally distributed effects. The optimum criteria used are based on the variances of the traditional analysis of variance estimators of the variance components. Exact solutions are compared to earlier results based on lower bounds of the sampling variances. Comparisons are also made to the large-sample variances of the estimates based on restricted maximum likelihood. Received February 2002  相似文献   

3.
This paper proposes a new rank-based test of extreme-value dependence. The procedure is based on the first three moments of the bivariate probability integral transform of the underlying copula. It is seen that the test statistic is asymptotically normal and its finite- and large-sample variance are calculated explicitly. Consistent plug-in estimators for the variance are proposed, and a fast algorithm for their computation is given. Although it is shown via counterexamples that no test based on the probability integral transform can be consistent, the proposed procedure achieves good power against common alternatives, both in finite samples and asymptotically.  相似文献   

4.
Summary When discrete autoregressive-moving average time series are fitted by least squares, both the residuals and their autocorrelations are for large n representable as singular linear transformations of the true errors (or white noise) and their autocomlations, respectively, and the matrices of these transformations arc both of the form I-X(X'X) -1X, where the rank of X is the number of parameters estimated. However, the large-sample properties of these two sets of statistics are fundamentally different, a phenomenon which is of considerable importance for the use of the residual autocorrelations in performing tests of fit of these models.  相似文献   

5.
This paper provides a control function estimator to adjust for endogeneity in the triangular simultaneous equations model where there are no available exclusion restrictions to generate suitable instruments. Our approach is to exploit the dependence of the errors on exogenous variables (e.g. heteroscedasticity) to adjust the conventional control function estimator. The form of the error dependence on the exogenous variables is subject to restrictions, but is not parametrically specified. In addition to providing the estimator and deriving its large-sample properties, we present simulation evidence which indicates the estimator works well.  相似文献   

6.
利用北京市两次全国基本单位普查所提供的大样本数据,以"街区"为基本空间分析单元,从不同空间层次,分析了北京生产者服务业空间变动的特征及结构模式.发现:两次普查间,北京生产者服务业整体处于空间集聚阶段;近郊区内沿为快速增长的核心地域,中心城增长速度缓慢,但并没有表现出明显的空间分散特征;"城八区集中分布,外围点状分布"的整体格局表现更为突出.  相似文献   

7.
An agency-theory model of IPO management retention is presented and empirically explored. The model is based upon the differences between the investment public’s and underwriters’ fears of the consequences of management entrenchment and other agency problems. The model suggests that IPO underpricing should be a curvilinear hump-shaped function of retention. A large-sample empirical exploration verifies the curvilinear relation.  相似文献   

8.
This paper proposes an alternative to maximum likelihood estimation of the parameters of the censored regression (or censored ‘Tobit’) model. The proposed estimator is a generalization of least absolute deviations estimation for the standard linear model, and, unlike estimation methods based on the assumption of normally distributed error terms, the estimator is consistent and asymptotically normal for a wide class of error distributions, and is also robust to heteroscedasticity. The paper gives the regularity conditions and proofs of these large-sample results, and proposes classes of consistent estimators of the asymptotic covariance matrix for both homoscedastic and heteroscedastic disturbances.  相似文献   

9.
Some sampling properties of Zellner's (1978) MELO estimates of structural coefficients of linear simultaneous equation models are examined by a series of sampling experiments. The MELO estimates appear to have more pronounced biases in estimating structural coefficients than the 2SLS estimates. However, MELO is found to outperform 2SLS according to several criteria, including MSE and MAE in a wide range of situations generated by varying structural coefficients, the variance-covariance matrix of structural disturbances, and the sample size. The magnitude of absolute sampling errors, the estimation of the variance of structural disturbances, and the large-sample standard errors are also compared among OLS, 2SLS, and MELO.  相似文献   

10.
A very important aspect of virtually any kind of systematic investigation is to be able to identify whether two entities are different, and, almost equivalently, whether they are the same. We need to be sure that measurements made at different time in different places by different experimenters are equivalent. To do this in the social sciences, the procedure of equating is necessary to be able to compare measurements made using different instruments. Small sample sizes can lead to apparent jaggedness in the formulae for equating two quantities, and some kind of smoothing procedure is frequently necessary when dealing with relatively small samples. A large-sample formula is developed for the standard error of moving average smoothed equipercentile equating on a single sample. An example is given of the application in equating two versions of a reading test, and the results are verified using a bootstrap procedure. The large sample formula gives a result that is close to the bootstrap procedure, except at very sparse frequencies.  相似文献   

11.
Sensitive topics or highly personal questions are often being asked in medical, psychological and sociological surveys. This paper proposes two new models (namely, the triangular and crosswise models) for survey sampling with the sensitive characteristics. We derive the maximum likelihood estimates (MLEs) and large-sample confidence intervals for the proportion of persons with sensitive characteristic. The modified MLEs and their asymptotic properties are developed. Under certain optimality criteria, the designs for the cooperative parameter are provided and the sample size formulas are given. We compare the efficiency of the two models based on the variance criterion. The proposed models have four advantages: neither model requires randomizing device, the models are easy to be implemented for both interviewer and interviewee, the interviewee does not face any sensitive questions, and both models can be applied to both face-to-face personal interviews and mail questionnaires.  相似文献   

12.
In this paper we derive the large-sample asymptotic joint distribution of the statistics used as fundamental measures of central location, concentration, skewness and kurtosis in the analysis of circular data. The importance of the distributional result in relation to inference for the corresponding population measures is illustrated, with various new confidence set constructions being derived and applied in the analysis of data from an animal orientation experiment.  相似文献   

13.
On Conditional Density Estimation   总被引:1,自引:0,他引:1  
With the aim of mitigating the possible problem of negativity in the estimation of the conditional density function, we introduce a so-called re-weighted Nadaraya-Watson (RNW) estimator. The proposed RNW estimator is constructed by a slight modification of the well-known Nadaraya-Watson smoother. With a detailed asymptotic analysis, we demonstrate that the RNW smoother preserves the superior large-sample bias property of the local linear smoother of the conditional density recently proposed in the literature. As a matter of independent statistical interest, the limit distribution of the RNW estimator is also derived.  相似文献   

14.
The valuation of Asian options is complicated because the arithmetic average of lognormal random variables is no longer lognormal. Furthermore, the stochastic volatility inherent in financial asset prices is easily observed. However, few academic studies consider the pricing and hedging of Asian options with stochastic volatility, despite the popularity of such options. This study extends the work of Hull and White (1987) and integrates the Taylor series expansion technique to derive an approximate analytic solution for Asian options with stochastic volatility. Numerical experiments show that the proposed approximate analytic solution performs favorably and is computationally efficient compared with large-sample simulations. The approximate analytic solution provides a practical approach for pricing and hedging Asian options with stochastic volatility and is both easy to implement and desirable in terms of computing speed.  相似文献   

15.
In this paper, we consider the large-sample relation between returns and lagged order flows over horizons of up to 2 months. The analysis is motivated by work in market microstructure which suggests that the effects of inventory control on stock returns should be discernible over horizons longer than those considered in the literature. We begin our analysis by developing a simple model of inventory effects in the presence of public information. Using mid-quote return data, we then find some evidence of return predictability using order flows, even after controlling for lagged returns, which is consistent with our theoretical setting. The relation is present only for negative imbalances and is stronger in large firms rather than small ones. Overall, the analysis is consistent with the notion that inventory control effects span several weeks.  相似文献   

16.
Excess volatility and regression tests have resulted in apparent rejections of the present-value relation when ex-post price approximations are employed. These approximations are based upon a sample terminal condition for prices, are not ergodic time-series, and do not result in statistics with readily calculable standard errors. Kleidon (1986a) has demonstrated that ex-post price approximations can subtly affect the reliability of certain volatility tests. We use a bootstrapped cointegration model to demonstrate some of these same effects in Mankiw, Romer and Shapiro's (1985) volatility statistics. The volatility statistics rarely have positive expected value in finite samples and still do not reject the presentvalue relation. Approximations based upon a ‘rolling’ terminal condition result in volatility statistics which have calculable large-sample errors, but even these standard errors greatly overstate the accuracy of volatility statisics in small samples. Regression tests of the present value relation are also affected by the price approximations.  相似文献   

17.
Most research into the relationship between health and work has been limited to ad hoc studies: few studies have been based on large-sample surveys directed to the general population. We propose here approaches to developing work-related health indicators from currently collected National Labour Force Surveys, in particular the Italian Labour Force Survey-ISTAT. Four potential indicators are proposed: temporary reduction in working ability (TRWA), continued reduction in working ability (CRWA), permanent inability to work (PIW), and exclusion from the active population (EAP). Our analysis indicates that CRWA and EAP are highest among manual workers, consistent with the well-described relationship between job class and health status. This approach provides an opportunity to monitor the relative health status of workers on a continuing basis using readily available, population-based data and to conduct additional analyses on the basis of occupational stratification.  相似文献   

18.
企业社会责任层次论是西方企业社会责任理论中最具代表性的理论,但在中国情境下,这种理论的缺陷直接制约了我国企业社会责任理念的建立。为此,探索中国情境下的企业社会责任维度,构建一个适合中国本土情境的企业社会责任模型,是目前中国企业社会责任理论研究界的一个重要历史使命。本研究通过设计一个开放式问卷进行大样本的调研和通过深度访谈的途径,获取了中国企业社会责任状况的第一手资料,通过质化分析,共得到中国企业社会责任的15个概念维度、6个范畴,在此基础上,构建起中国本土特色的企业社会责任人体模型。比较分析的结果表明,中国与西方国家企业社会责任的概念范畴既有相同之处,又存在显著的差异,这进一步表明在中国企业社会责任方面开展高水平本土化研究的必要性。  相似文献   

19.
Error bounds depending explicitly on parameters of the problem are given for large-sample approximations to the central and noncentral distributions ofFriedman's [1937]x r 2 statistic,Steel's [1959] statistics for comparingr treatments with a control, andNemenyi's [1963] statistics for pair-wise comparisons among all treatments. These bounds are of ordero(N –1/2); an improved bound of ordero (N –r/(r+1)) is given forFriedman's statistic in the central case. Applications yield bounds on the actual type 1 and type 2 error probabilities in terms of their normal-theory approximations.Supported in part by ONR Contract N00014-72A-0136-003 from the U.S. Office of Naval Research.  相似文献   

20.
We study the problem of testing hypotheses on the parameters of one- and two-factor stochastic volatility models (SV), allowing for the possible presence of non-regularities such as singular moment conditions and unidentified parameters, which can lead to non-standard asymptotic distributions. We focus on the development of simulation-based exact procedures–whose level can be controlled in finite samples–as well as on large-sample procedures which remain valid under non-regular conditions. We consider Wald-type, score-type and likelihood-ratio-type tests based on a simple moment estimator, which can be easily simulated. We also propose a C(α)-type test which is very easy to implement and exhibits relatively good size and power properties. Besides usual linear restrictions on the SV model coefficients, the problems studied include testing homoskedasticity against a SV alternative (which involves singular moment conditions under the null hypothesis) and testing the null hypothesis of one factor driving the dynamics of the volatility process against two factors (which raises identification difficulties). Three ways of implementing the tests based on alternative statistics are compared: asymptotic critical values (when available), a local Monte Carlo (or parametric bootstrap) test procedure, and a maximized Monte Carlo (MMC) procedure. The size and power properties of the proposed tests are examined in a simulation experiment. The results indicate that the C(α)-based tests (built upon the simple moment estimator available in closed form) have good size and power properties for regular hypotheses, while Monte Carlo tests are much more reliable than those based on asymptotic critical values. Further, in cases where the parametric bootstrap appears to fail (for example, in the presence of identification problems), the MMC procedure easily controls the level of the tests. Moreover, MMC-based tests exhibit relatively good power performance despite the conservative feature of the procedure. Finally, we present an application to a time series of returns on the Standard and Poor’s Composite Price Index.  相似文献   

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