Patents,R&;D and lag effects: evidence from flexible methods for count panel data on manufacturing firms

This paper investigates the relationship between patents and research and development expenditures using new longitudinal patent data at the firm level for the U.S. manufacturing sector from 1982 to 1992. The paper also develops a new class of count panel data models based on series expansion of the distribution of individual effects. Estimation results from various distributed lag and dynamic multiplicative panel count data models show that the contemporaneous relationship between patenting and R&D expenditures continues to be strong, accounting for over 60% of the total R&D elasticity. The lag effects are higher than have previously been found for the 1970s data. We would like to thank Chris Bollinger, Bronwyn Hall and Paula Stephan for useful comments on the previous version of the paper. Earlier versions were presented at the 11th International Conference on Panel Data, Texas A&M University, the Midwest Econometrics Group Meeting, and the Annual Conference of the Southern Economic Association.     

如何有效提高广西高职会计学原理课程的教学质量

会计学原理又称基础会计学,是高职高专经济管理专业的专业基础课程,更是会计专业课程的奠基石。文章结合广西高职会计专业学生的特点,从教学材料和教学方法两大方面论述如何提高会计学原理课程的教学质量。     

Forecasting and turning point predictions in a Bayesian panel VAR model

We provide methods for forecasting variables and predicting turning points in panel Bayesian VARs. We specify a flexible model, which accounts for both interdependencies in the cross section and time variations in the parameters. Posterior distributions for the parameters are obtained for hierarchical and for Minnesota-type priors. Formulas for multistep, multiunit point and average forecasts are provided. An application to the problem of forecasting the growth rate of output and of predicting turning points in the G-7 illustrates the approach. A comparison with alternative forecasting methods is also provided.     

The over-optimism among experts in assessment and foresight

It is still disputed whether foresight exercises should be based on top-expert assessments or on a broader base of less specialised experts, and whether the self-rating of experts is an acceptable method. Using the German 1993 and the Austrian 1998 Technology Delphis, this study addresses both questions. Self-rating is, in fact, an appropriate method for selecting experts. But the assessment of self-rated top experts tend to suffer from an optimism bias due to the experts' involvement and their underestimation of realisation and diffusion problems. The degree of optimism is positively correlated with the degree of self-rated knowledge, and it is more pronounced for the least pioneering and for organizational innovations. Experts with top self-ratings working in business have a stronger optimism bias than those working in the academia or in the administration: Consistent with the insider hypothesis, they are most optimistic with regard to realisation, innovativeness, and potential leadership in economic exploitation. Given the optimism bias, foresight exercises should base their panels on a fair mixture of experts of different grades, with different types of knowledge and affiliation, and not only on top specialists of the respective field. Delphi-type exercises, therefore, offer an advantage relative to forum groups or small panels of specialists.     

企业投资项目比选决策方法研究

由于信息不对称或者有些投资项目本身没有先例可循,企业投资项目存在很大风险.为了较全面地考察项目投资所面临的各种因素,作出合理的项目投资决策,采用多属性决策中确定属性权重的熵权法联合决策者对属性重要性认识的主观权重和用于排序比较的TOPSIS法,为企业投资项目的比选决策提供一种新的决策方法.该方法综合考虑了决策者的主观权重和投资项目各影响因素信息之间固有的客观权重、综合考虑了风险和收益的多方面因素对投资项目作出比选决策.最后举一项目投资比选实例加以说明.     

Subsampling the distribution of diverging statistics with applications to finance

In this paper we propose a subsampling estimator for the distribution of statistics diverging at either known or unknown rates when the underlying time series is strictly stationary and strong mixing. Based on our results we provide a detailed discussion of how to estimate extreme order statistics with dependent data and present two applications to assessing financial market risk. Our method performs well in estimating Value at Risk and provides a superior alternative to Hill's estimator in operationalizing Safety First portfolio selection.     

粘土稳定剂防膨率评价方法分析

防膨率是筛选和评价粘土稳定剂产品的重要指标。为了提高粘土稳定剂防膨率测定方法的准确性和重现性,结合实际检测工作,逐一分析了页岩膨胀仪法、具塞量筒法和离心法测定粘土稳定剂防膨率的误差来源和影响因素。结果表明:离心法可以减少仪器、环境、空白等方面产生的误差,测试实验条件下的相对标准偏差在1%以下。     

Comparative evaluation of a teaching innovation in accounting education: intensive learning in a seminar format

This paper reports a teaching innovation involving intensive learning and the evaluation of that innovation. A review of the literature reveals a lack of research about how effective intensive programmes are in enhancing student learning. In this study the performance of students studying accounting during an intensive summer-school in seminar format was compared with those studying during the regular semester in a lecture and tutorial format. Performance was compared by reference to students' grades and the understanding and retention of a key concept in the subject. Student study habits and the experiences of staff and students who participated in the summer-school were also evaluated. This study concluded that summer-school students' performance was better than regular semester students in the accounting subject studied. Their performance was equivalent or better than the regular semester students in the three other subjects studied in first semester. Summer-school students demonstrated a more complete understanding of a key concept than did the students in the regular semester, with this difference sustained after two years. There was a positive response to the summer-school by those staff and students who participated.     

空乘专业学生急救实训方法

急救在空中乘务工作中是非常重要的一项技术,它直接关系到飞行安全和旅客的安全。根据当前空乘专业学生急救教学的实际以及就业反馈情况,分析急救实训教学改革的必要性,通过研究急救实训教学中培养和提高空乘专业学生急救能力的可行性实训方法,对空乘专业学生核心能力培养提供积极的探索。     

飞参数据判读方法研究

飞参数据判读是将记录参数转化为机务维护信息的关键.本文研究了飞参数据判读的内容,详细分析了飞参判读的原则;并对飞参数据判读中常用的四种方法进行了阐述,同时举例进行了说明.