考虑违约距离的上市公司危机预警模型研究

在上市公司财务危机预警中,违约距离起着重要的不可替代的作用,仅考虑财务指标并不足以完全解释企业财务危机发生的原因.文章应用Merton模型对2002～2004年ST公司和相应配对公司的危机发生之前的违约距离进行了研究,发现危机公司违约距离在危机发生前第三年明显低于正常公司的相应值,违约距离比传统财务指标能更早地预警到企业财务危机的发生.结合违约距离因素的危机预警模型能更明显地提高模型的危机判断正确率.     

改革以来中国农村发展地区差距分析

本文在扩展农业部门新古典经济增长模型的基础上,构建了基于农业生产率指数和农村地区劳动力就业结构的农村发展指标,以此来衡量农村发展水平及其变化状况.为了考察中国农村发展地区差距的变化趋势,我们采用面板数据单位根检验的不同方法对其收敛性进行了严格的计量检验.检验结果显示,在考虑了时间和省份特殊效应、序列相关等因素的影响后,中国各省农村发展差距以及东中西部地区农村发展的内部差距均存在条件性β收敛.     

ML– and semiparametric estimation in logistic models with incomplete covariate data

ML–estimation of regression parameters with incomplete covariate information usually requires a distributional assumption regarding the concerned covariates that implies a source of misspecification. Semiparametric procedures avoid such assumptions at the expense of efficiency. In this paper a simulation study with small sample size is carried out to get an idea of the performance of the ML–estimator under misspecification and to compare it with the semiparametric procedures when the former is based on a correct assumption. The results show that there is only a little gain by correct parametric assumptions, which does not justify the possibly large bias when the assumptions are not met. Additionally, a simple modification of the complete case estimator appears to be nearly semiparametric efficient.     

Panel unit root tests under cross-sectional dependence

In this paper alternative approaches for testing the unit root hypothesis in panel data are considered. First, a robust version of the Dickey-Fuller t -statistic under contemporaneous correlated errors is suggested. Second, the GLS t -statistic is considered, which is based on the t -statistic of the transformed model. The asymptotic power of both tests is compared against a sequence of local alternatives. To adjust for short-run serial correlation of the errors, we propose a pre-whitening procedure that yields a test statistic with a standard normal limiting distribution as N and T tends to infinity. The test procedure is further generalized to accommodate individual specific intercepts or linear time trends. From our Monte Carlo simulations it turns out that the robust OLS t -statistic performs well with respect to size and power, whereas the GLS t -statistic may suffer from severe size distortions in small and moderate sample sizes. The tests are applied to test for a unit root in real exchange rates.     

企业集团母子公司财务控制系统构建研究

企业集团是以产权关系为纽带 ,由众多企业法人共同组成的联合体。企业集团母子公司财务控制系统是企业集团核心管理内容之一。笔者通过自身的工作经验并结合理论研究认为 :企业集团母子公司财务控制系统是由财务人员控制系统、财务制度控制系统、财务目标控制系统和财务信息控制系统等构建的有机整体 ,企业集团管理当局应提供良好的人文环境和机制环境 ,保证其高效、及时、完整、良好地运行 ,保持企业集团的可持续发展 ,才能实现企业集团价值最大化     

矿区生态经济若干问题探讨

本文着重探讨了矿区资源开发中生态经济系统的特征；铜矿资源的珍贵性；矿区自然资源和生态环境以及劳动力资源的脆弱易损性；露采优先方针的重要性；矿区生态、经济、社会三者效益的统一性；21世纪采矿与环境协调发展的新概念和新技术、新工艺。     

Seasonal decomposition and forecasting of telecommunication data: A comparative case study

In this paper, forecasting models for the monthly outgoing telephone calls in a University Campus are presented. The data have been separated in the categories of international and national calls as well as calls to mobile phones. The total number of calls has also been analyzed. Three different methods, namely the Seasonal Decomposition, Exponential Smoothing Method and SARIMA Method, have been used. Forecasts with 95% confidence intervals were calculated for each method and compared with the actual data. The outcome of this work can be used to predict future demands for the telecommunications network of the University.     

Linking Public Investment to Private Investment. The Case of Spanish Regions

Public investment constitutes one of the main instruments of regional policies. The existence of a direct link between infrastructure and regional income per capita is usually accepted. Literature also describes a positive effect of public investment on private capital accumulation. This paper seeks to provide new empirical evidence on this latter relationship for the case of Spanish regions over the period 1965–1997 using panel data methodology. The results show a positive effect of productive and social public investment (especially in education) on private investment. The spillover effects generated by the productive infrastructures located in other regions do not seem to encourage the private investment in neighbouring regions. Public consumption and interest rate exert a negative influence on private capital accumulation. These results are robust to changes in the econometric specification.     

Web数据挖掘中XML技术的应用研究

随着网络技术的发展,网上的信息资源越来越丰富,怎样对Web上海量的数据信息进行深层次的应用成了当今数据库技术的研究热点。文章针对Web上数据的特点和目前Web数据挖掘存在的挑战,结合XML语言的技术特点,主要探讨了XML技术在Web数据挖掘中的重要应用。     

The price relationship between organic and non-organic vegetables in the U.S.: evidence from Nielsen scanner data

This study investigates price relationships between organic and conventional carrots, tomatoes, and lettuce in the U.S. utilizing Nielsen scanner data from 2006–2015. We employ a threshold vector error correction model (TVECM), threshold vector autoregressive model (TVAR), and threshold cointegration test to test whether market integration exists between organic and conventional vegetables as well as the existence of asymmetric price transmission. The results find positive long-run relationships between organic and conventional prices of carrots and tomatoes and show the existence of asymmetric price transmission in price pairs of lettuce and tomatoes. Our findings suggest that the price relationship between organic and conventional vegetables varies by characteristics, such as shelf life, volatility in the price premium, and substitutability.