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991.
Tests for parametric nonhomogeneous and homogeneous Markov processes are given. Asymptotic distribution of test statistics is investigated. Tests for various well-known models are discussed as examples.  相似文献   
992.
In general, consumer utility of network goods is affected by the entire network size. The socio-cultural-economic affinities of consumers influence the network externality processes. In this work, we treat a consumer decision as a consumer decision dynamic process. We then formulate a dynamic structural representation of a consumer network structure, structure of utility function and decision rule under the influence of local network externality concept. This formulation generates a mathematical model for a consumer decision dynamic process. The byproduct of the dynamic model leads to an agent-based simulation model. The simulation model is used to investigate different types of consumer decision dynamic market equilibriums. Moreover, prototype illustrations are given to exhibit the association between network attributes and its market equilibriums.  相似文献   
993.
This study explores gender differences in positive perceptions, anxiety, and depression among mothers and fathers of children with intellectual disabilities (IDs). We examined the relationship between these variables and certain characteristics of both the child (age and severity of disability) and the parents (age, educational level, and employment status). A sample of 60 mother/father couples who had children with IDs completed the Positive Contributions Scale to measure their positive perceptions, and the Hospital Anxiety and Depression Scale to assess their level of anxiety and depression. Bivariate analyses were used to determine differences between fathers and mothers as regards their positive perceptions and levels of anxiety and depression. A logistic regression model was then applied to identify which of the variables might be significant predictors of the gender differences observed among parents. Both mothers and fathers had positive perceptions of their children with IDs that co-existed with symptoms of anxiety and depression, with scores being higher among mothers. The predictive analysis of gender showed that individual variables (such as the employment status of both parents) may explain these differences.  相似文献   
994.
Employee Stock Ownership Programs (ESOPs) have long been promoted as a motivational tool: employees become profit‐minded owners. Latterly, however, more ESOPs are being used as part of a takeover defense: here the ESOPs main purpose is to put more company stock in friendly hands—the employees—who, like existing management, could suffer layoffs, etc. in a hostile takeover. We find that, as a group, only the takeover‐related ESOPs are associated with increased leverage (itself a takeover defense). Non‐target firms show no long‐term increase in debt‐to‐assets. We find little evidence to support the motivation hypothesis: while actual labor costs are lower for ESOP firms, after industry‐adjusting they tend to be unaffected or higher. We find that a few measures of firm financial performance [return‐on‐equity (ROE), return‐on‐assets (ROA), net profit margin (NPM)] do improve significantly, but this appears to be largely a short‐term effect. Industry‐adjusted holding period returns appear to be unaffected by the ESOP; however, ESOP firms that leverage show evidence of long‐term market underperformance. We conclude that ESOPs provide, at best, only a short‐term boost to corporate performance. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
995.
996.
A simple model of employment contracting is employed to examine the effectiveness of just‐cause provisions in alleviating employer opportunism in two types of efficiency wage contracts—standard contracts, in which wages exceed the worker's marginal contribution, and deferred wages, which are paid after a period of tenure in the firm. It is argued that just‐cause employment policies are necessary and sufficient to prevent employer opportunism when standard efficiency wages are utilized. However, just‐cause policies are not sufficient to deter employer opportunism when employment contracts are of the delayed‐payment type. In these contracts, other contractual provisions, such as severance provisions, are also necessary. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
997.
This paper uses a choice experiment to study citizens' preferences for effort-sharing rules for reducing carbon dioxide emissions. For a given global cost and level of emission reduction, we study the willingness to pay for various rules that imply different distributions of the cost between EU, the US, China and Africa. The focus of this paper is on the use of two different treatments, one where the respondents were informed about the country (or country group) names and one where the names were replaced with anonymous labels A-D. This allows us to test whether people's preferences for effort-sharing rules depend on the framing of the problem. We find that the ranking of the rules and the strength of the preferences are not significantly different between the two treatments, and hence we find no evidence of ingroup bias in preferences for effort-sharing rules.  相似文献   
998.
999.
This paper presents a model of innovations and endogenous economic growth with two main assumptions: first, the cost of searching for innovations differs across innovations, and second, innovations take time to find. The paper shows that given these two assumptions together, competition leads to patent races and to duplication of innovative activity. The paper then shows that duplication significantly reduces the effect of scale on growth. It also shows that competitive R&D creates too much research on easy innovations, and too little research on the difficult ones. Finally, the paper shows that risk sharing might increase duplication and reduce growth.  相似文献   
1000.
Online labor markets have great potential as platforms for conducting experiments. They provide immediate access to a large and diverse subject pool, and allow researchers to control the experimental context. Online experiments, we show, can be just as valid—both internally and externally—as laboratory and field experiments, while often requiring far less money and time to design and conduct. To demonstrate their value, we use an online labor market to replicate three classic experiments. The first finds quantitative agreement between levels of cooperation in a prisoner’s dilemma played online and in the physical laboratory. The second shows—consistent with behavior in the traditional laboratory—that online subjects respond to priming by altering their choices. The third demonstrates that when an identical decision is framed differently, individuals reverse their choice, thus replicating a famed Tversky-Kahneman result. Then we conduct a field experiment showing that workers have upward-sloping labor supply curves. Finally, we analyze the challenges to online experiments, proposing methods to cope with the unique threats to validity in an online setting, and examining the conceptual issues surrounding the external validity of online results. We conclude by presenting our views on the potential role that online experiments can play within the social sciences, and then recommend software development priorities and best practices.  相似文献   
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