信息产业对经济增长的贡献研究——以桂林市为例

本文通过引入时间序列计量经济学中的协整分析理论与方法,对1995-2005年间桂林市信息产业在经济增长中的影响进行定量研究,实证信息产业对GDP增长的影响显著,两者存在长期均衡的协整关系.信息产业发展与经济增长是格兰杰因果关系.     

A Goal-Setting and Feedback Intervention to Increase ID-Checking Behavior: An Assessment of Social Validity and Behavioral Impact

A participative goal-setting and feedback intervention increased cashiers' identification-checking behavior at a large grocery store. The cashiers' identification-checking percentages increased from 0.2% at baseline to 9.7% during the intervention phase and then declined to 2.3% during withdrawal. At the control store, the percentages of identification-checked purchases were 0.3%, 0.4%, and 0.7%, respectively, during the A-B-A phases at the intervention store. A comprehensive social-validity assessment showed ID-checking to be accepted by both cashiers and customers.     

An Assessment of the Italian 2007 Complementary Social Security Reform: A Simulation Approach

In this paper we aim at assessing the outcomes of the 2007 Italian reform of the complementary social security scheme and at identifying the determinants behind them. The reform provided workers with relevant incentives to switch the investment of about 7 per cent of their gross yearly wages from a firm‐managed scheme (which took the form of a termination indemnity payment, the Trattamento di Fine Rapporto scheme) to an external pension fund. We provide a theoretical framework to model the workers' problem of choosing between these two different forms of complementary social security schemes and we then perform an agent‐based simulation taking into account all the details of the reform. Differently from previous contributions, we stress the impact that the investment decision has on the financial health of firms and, consequently, on workers' employment stability. Our simulations are able to replicate the Italian data in terms of adhesion rates to complementary social security and also to identify some of the key determinants of that outcome, such as fiscal incentives, individual preferences, the working of both the Italian labour and the financial markets and the productive structure of the Italian economy.     

An Integrated Methodology for Assessment and Selection of the Project Risk Response Actions

In a systematic process of project risk management, after risk assessment is implemented, the risk analysts encounter the phase of assessment and selection of the project risk response actions (RA). As indicated by many researchers, there are less systematic and well-developed solutions in the area of risk response assessment and selection. The present article introduces a methodology including a modeling approach with the objective of selecting a set of RA that minimizes the undesirable deviation from achieving the project scope. The developed objective function comprises the three key success criteria of a project, namely, time, quality, and cost. Our model integrates overall project management into the project risk response planning (P2RP). Furthermore, the proposed model stresses on an equivalent importance for both "risk" and "response." We believe that applying the proposed model helps the project risk analyst in most effective and efficient manner dealing with his or her complicated RA selection problems. The application of the proposed model was implemented in projects in the construction industry in which it showed tremendous time, cost, and quality improvements.     

Quantitative Assessment of Exposure to the Mycotoxin Ochratoxin A in Food

This article presents the methodology and the simulation results concerning the quantitative assessment of exposure to the fungus toxin named Ochratoxin A (OA) in food, in humans in France. We show that is possible to provide reliable calculations of exposure to OA with the conjugate means of a nonparametric-type method of simulation, a parametric-type method of simulation, and the use of bootstrap confidence intervals. In the context of the Monte Carlo simulation, the nonparametric method takes into account the consumptions and the contaminations in the simulations only via the raw data whereas the parametric method depends on the random samplings from distribution functions fitted to consumption and contamination data. Our conclusions are based on eight types of food only. Nevertheless, they are meaningful due to the major importance of these foodstuffs in human nourishment in France. This methodology can be applied whatever the food contaminant (pesticides, other mycotoxins, Cadmium, etc.) when data are available.     

Life-Cycle Assessment in Relation to Risk Assessment: An Evolving Perspective

A life-cycle approach takes a cradle-to-grave perspective of a product's numerous activities from the raw material extraction to final disposal. There have been recent efforts to develop life-cycle assessment (LCA) to assess both environmental and human health issues. The question then arises: what are the capabilities of LCA, especially in relation to risk assessment? To address this question, this paper first describes the LCA mass-based accounting system and then analyzes the use of this approach for environmental and human health assessment. The key LCA limitations in this respect are loss of spatial, temporal, dose-response, and threshold information. These limitations affect LCA's capability to assess several environmental issues, and human health in particular. This leads to the conclusion that LCA impact assessment does not predict or measure actual effects, quantitate risks, or address safety. Instead, LCA uses mass loadings with simplifying assumptions and subjective judgments to add independent effects and exposures into an overall score. As a result, LCA identifies possible human health issues on a systemwide basis from a worst case, hypothetical hazard perspective. Ideally, the identified issues would then be addressed by more detailed assessment methods, such as risk assessment.     

An Examination of a Theory of Embodied Social Presence in Virtual Worlds*

In this article, we discuss and empirically examine the importance of embodiment, context, and spatial proximity as they pertain to collaborative interaction and task completion in virtual environments. Specifically, we introduce the embodied social presence (ESP) theory as a framework to account for a higher level of perceptual engagement that users experience as they engage in activity‐based social interaction in virtual environments. The ESP theory builds on the analysis of reflection data from Second Life users to explain the process by which perceptions of ESP are realized. We proceed to describe implications of ESP for collaboration and other organizational functions.     

Risk Assessment Based on Financial Data: Market Response to Airline Accidents

The risk of catastrophic failures, for example in the aviation and aerospace industries, can be approached from different angles (e.g., statistics when they exist, or a detailed probabilistic analysis of the system). Each new accident carries information that has already been included in the experience base or constitutes new evidence that can be used to update a previous assessment of the risk. In this paper, we take a different approach and consider the risk and the updating from the investor's point of view. Based on the market response to past airplane accidents, we examine which ones have created a surprise response and which ones are considered part of the risk of the airline business as previously assessed. To do so, we quantify the magnitude and the timing of the observed market response to catastrophic accidents, and we compare it to an estimate of the response that would be expected based on the true actual cost of the accident including direct and indirect costs (full-cost information response). First, we develop a method based on stock market data to measure the actual market response to an accident and we construct an estimate of the full-cost information response to such an event. We then compare the two figures for the immediate and the long-term response of the market for the affected firm, as well as for the whole industry group to which the firm belongs. As an illustration, we analyze a sample of ten fatal accidents experienced by major US domestic airlines during the last seven years. In four cases, we observed an abnormal market response. In these instances, it seems that the shareholders may have updated their estimates of the probability of a future accident in the affected airlines or more generally of the firm's future business prospects. This market reaction is not always easy to explain much less to anticipate, a fact which management should bear in mind when planning a firm's response to such an event.     

Situated Food Safety Risk and the Influence of Social Norms

Previous studies of risk behavior observed weak or inconsistent relationships between risk perception and risk-taking. One aspect that has often been neglected in such studies is the situational context in which risk behavior is embedded: Even though a person may perceive a behavior as risky, the social norms governing the situation may work as a counteracting force, overriding the influence of risk perception. Three food context studies are reported. In Study 1 (N = 200), we assess how norm strength varies across different social situations, relate the variation in norm strength to the social characteristics of the situation, and identify situations with consistently low and high levels of pressure to comply with the social norm. In Study 2 (N = 502), we investigate how willingness to accept 15 different foods that vary in terms of objective risk relates to perceived risk in situations with low and high pressure to comply with a social norm. In Study 3 (N = 1,200), we test how risk-taking is jointly influenced by the perceived risk associated with the products and the social norms governing the situations in which the products are served. The results indicate that the effects of risk perception and social norm are additive, influencing risk-taking simultaneously but as counteracting forces. Social norm had a slightly stronger absolute effect, leading to a net effect of increased risk-taking. The relationships were stable over different social situations and food safety risks and did not disappear when detailed risk information was presented.     

An Examination of the Economic Circumstances Surrounding Decisions to Capitalize Brands

The paper reports both the results of an empirical investigation into the effects of the decisions of 13 UK companies to include brands in their published balance sheets on the prices of their shares, and also an examination of the motivations for these decisions from a costly contracting perspective. Price gains appear to be positively associated with the proportionate increase in reported net assets caused by capitalizing brands. On the other hand, when allowance is made for the contemporaneous release of other information, little, if any, of the share price behaviour around the announcement dates can be attributed to the capitalization of brands - a finding consistent either with the capital market having already formed unbiased expectations of brand values prior to disclosure, or with ills having serious doubts about the credibility of the valuations. Consistent with a costly contracting perspective of accounting method choice, we found that brand capitalization had a marked impact on reported gearing levels and more or less eliminated the higher gearing levels of capitalizing firms relative to similar companies, particularly as far as late adopting firms were concerned. Brand capitalization also had a particularly marked impact on book-to-market-equity ratios; capitalization served to increase the ratios of capitalizing firms to approximately the levels observed on the non-capitalizing controls.     

Modeling the Public Health System Response to a Terrorist Event in the Food Supply

We have developed a simulation model to quantify and characterize the response of the public health system and the impact of public health advisories in the event of an intentional contamination of the food supply. The model has three components: (1) definition of individual exposure over time and the outcomes of exposure, (2) definition of the geographical dispersal of exposures, and (3) response of the public health authorities to symptomatic individuals. The model explicitly considers the variation in the multiple interrelated facets of the response system, including differences among individuals' responses to exposure, variation between health care providers, and the subsequent processing of samples and confirmation of cases. To illustrate use of the model, case studies with  Escherichia coli  O157:H7 and  Salmonella  spp. in three categories of food vehicle were compared. The level of detail required to run the public health component of the model is not trivial. While some data may not be available for hazards of particular interest in potential bioterrorism events, the application of expert judgment permits comparisons between different agents, different system reactions, and other assumptions within the system. The model provides the capacity to study the impact of system changes, to compare scenarios and to quantify the benefits of improvement in terms of averted exposures and risk reduction, and constitutes a significant aid to understanding and managing these threats. Essentially, the model provides an explicit valuation of time saved in the identification and intervention in terrorist events in the food supply.     

Public Perceptions of the Potential Hazards Associated with Food Production and Food Consumption: An Empirical Study

Although public perceptions of food-related hazards receive much media comment and debate, the research literature on such perceptions is sparse and piecemeal. In the reported study, 216 people completed a questionnaire relating to their perceptions of the "risk characteristics" of potential hazards associated with various aspects of food production and food consumption. Responses were examined via principal-components analysis to obtain a structural representation of risk perception of the kind provided by Fischhoff, Slovic, and their colleagues in their seminal psychometric work.^(1,2) A three-component solution accounting for 87% of the variance was obtained, with the dimensions labeled as "severity,""unknown," and "number of people exposed." The findings also yielded information pointing to evidence of the phenomenon of unrealistic optimism. We conclude that our findings offer a useful base upon which further in-depth research integrating different perspectives on risk perception with respect to food-related hazards may be developed.     

Forty Years of Food Safety Risk Assessment: A History and Analysis

Before the founding of the Society for Risk Analysis (SRA) in 1980, food safety in the United States had long been a concern, but there was a lack of systematic methods to assess food-related risks. In 1906, the U.S. Congress passed, and President Roosevelt signed, the Pure Food and Drug Act and the Meat Inspection Act to regulate food safety at the federal level. This Act followed the publication of multiple reports of food contamination, culminating in Upton Sinclair's novel The Jungle, which highlighted food and worker abuses in the meatpacking industry. Later in the 20th century, important developments in agricultural and food technology greatly increased food production. But chemical exposures from agricultural and other practices resulted in major amendments to federal food laws, including the Delaney Clause, aimed specifically at cancer-causing chemicals. Later in the 20th century, when quantitative risk assessment methods were given greater scientific status in a seminal National Research Council report, food safety risk assessment became more systematized. Additionally, in these last 40 years, food safety research has resulted in increased understanding of a range of health effects from foodborne chemicals, and technological developments have improved U.S. food safety from farm to fork by offering new ways to manage risks. We discuss the history of food safety and the role risk analysis has played in its evolution, starting from over a century ago, but focusing on the last 40 years. While we focus on chemical risk assessment in the U.S., we also discuss microbial risk assessment and international food safety.     

以科学考评机制引领干部树立正确政绩观

树立正确的政绩观,落实科学的发展观,为全面建设小康社会、全力构建和谐社会奠定坚实的思想基础,是当前摆在全党特别是各级领导干部面前的一个重大而严肃的政治问题。胡锦涛同志曾经指出,要把树立正确的政绩观作为新时期党的建设新的伟大工程的重要内容,并     

中国人的上下级关系:整合构念的建立与初步检验

为建立更整合的SSG构念,基于多维度人际关系理论,提出SSG三维构念,认为上下级关系指在某一时刻存在于上下级之间的基于利益、情感和身份义务的连结。工具性、情感性、义务性是构成上下级关系的3个维度,由此发展出SSG类型构念初始模型。为检验理论,以调查与案例混合法收集并分析39对上下级关系的相关信息,基于分析结果形成SSG类型构念修正模型。经检验,修正后的SSG类型构念与案例有较高的相符程度。最终形成的SSG构念理论包括构念界定、维度内涵、维度的动态发展、维度构念与类型构念的对应关系和类型描述等内容。     

变革型领导行为对员工建言行为的影响研究

主要研究变革型领导行为对员工建言行为的影响及其中介作用机制。在中介作用机制的探讨上,主要从心理认知和社会交换的理论视角出发,侧重于分析心理安全知觉和领导部属交换的中介作用。研究采用问卷调查研究的方法,研究对象是广州5家高科技电子制造企业中的213名员工及其对应的213名领导。通过数据分析发现:变革型领导行为对员工建言行为有显著的正向影响,领导部属交换与心理安全知觉在其中起着完全中介的作用。