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51.
52.
American options in discrete time can be priced by solving optimal stopping problems. This can be done by computing so-called continuation values, which we represent as regression functions defined recursively by using the continuation values of the next time step. We use Monte Carlo to generate data, and then we apply smoothing spline regression estimates to estimate the continuation values from these data. All parameters of the estimate are chosen data dependent. We present results concerning consistency and the estimates’ rate of convergence.  相似文献   
53.
This paper proposes an experimental test to evaluate the performance of the serial cost sharing rule, originally proposed by Shenker [Sigmetrics, 241–242 (1990)] and then analyzed by Moulin and Shenker [Econometrica 60, 1009–1037 (1992)]. We report measures of the performance and efficiency of the serial mechanism by comparing the choices and payoffs attained by the subjects to the expected equilibrium allocations. Experimental evidence shows that learning is needed for the subjects to converge to the equilibrium strategy. However, in terms of efficiency, the serial mechanism leads to almost efficient allocations.  相似文献   
54.
Peltzman [Peltzman, S., 1984. Constituent interest and congressional voting. Journal of Law and Economics 27, 181–210] argues that if constituents’ economic interests have well-defined “winners and losers” and are appropriately measured, then constituents’ economic interests, and not legislator ideology, are the most important determinates of legislator voting. We test Peltzman's theory by examining senatorial voting on three mandated spending limitation bills. We find, consistent with Peltzman's theory, that the ratio of federal spending in a senator's state to federal taxes paid by that state, and not a senator's personal ideology, matters on legislation where there are well-defined economic “winners and losers.” This is particularly important because unlike other constituents’ economic interest measures that only impact a fraction of the constituency, the ratio of federal spending to federal taxes in a state represents the economic interests of all the constituents in a state.  相似文献   
55.
The importance of women on the bench and the influence of gender on judicial decision making has garnered much scholarly attention. We examine the voting behavior of male and female justices in 718 Fourth Amendment search and seizure votes cast on state Supreme Courts between 1980 and 2000. We find that women justices, controlling for institutional, political, and legal constraints, are more likely to rule in favor of the criminal defendant than their male brethren in cases decided after 1991 but not before. We also find women justices serving with female colleagues are more inclined to render liberal votes. We conclude the influence of gender may be evident in a wider variety of cases than those dealing with women's lives but that this influence is dependent upon the existence of a critical mass of women on the state court benches.  相似文献   
56.
We employed 4,095 couples from both waves of the National Survey of Families and Households (NSFH) to test a model of couple violence drawn from several theoretical perspectives. The outcome distinguishes among nonviolent couples and those experiencing either physical aggression or intense male violence. According to the model, background characteristics of couples are related to relationship stressors, which affect the risk of violence via their tendency to promote verbal conflict. Considerable support for the model was found. Couples were at higher risk for one or both forms of violence if they were younger at union inception, had been together for less time, were both in their first union, had only one partner who was employed, had a nontraditional woman paired with a traditional man, had at least one partner who abused substances, had more children, had more frequent disagreements, exhibited a more hostile disagreement style, or lived in an economically disadvantaged neighborhood. Moreover, the effects of stressors such as the number of children and couples' employment status disparities appear to be mediated by disagreement frequency and disagreement style.  相似文献   
57.
It is well known that the unimodal maximum likelihood estimator of a density is consistent everywhere but at the mode. The authors review various ways to solve this problem and propose a new estimator that is concave over an interval containing the mode; this interval may be chosen by the user or through an algorithm. The authors show how to implement their solution and compare it to other approaches through simulations. They show that the new estimator is consistent everywhere and determine its rate of convergence in the Hellinger metric.  相似文献   
58.
A firm deciding on its promotion practices will be concerned both with the efficient assignment of workers to tasks and with rewarding prior performance. This can result in a time-inconsistency problem because the promotion rule that is optimal at the time of the promotion decision may differ from the rule that is optimal before performance is determined. In this article I explore the role of time inconsistency in determining promotion practices. In particular, I show that the common practice of favoring internal candidates for promotion can be understood as a response by firms to the problem of time inconsistency.  相似文献   
59.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
60.
Technology Assessment (TA) is a problem oriented endeavour dealing with political, societal, ecological, etc. problems. Only in rare cases is one individual scientific discipline sufficient to assess these problems. Usually the perspectives of different scientific disciplines have to be combined in order to develop interdisciplinary based recommendations to act. In this paper a quality controlled interdisciplinary discussion process is described which encourages an expert group to generate argumentation chains cross-cutting the disciplinary boundaries. The role of ethical reflection in this procedure depends on the problem situation. Whenever a technical application is on the agenda which cannot be allocated to a so-called “business-as-usual” case, one would ask for ethical reflection. This contribution argues that this ethical reflection has to take place together with the interdisciplinary discussion due to two reasons. Firstly, the technical, economical, legal and social aspects are deeply cross-correlated with the ethical reflection. And secondly, participating in such interdisciplinary discussions enables an ethical reflection which keeps in touch with the real world. Two case studies dealing with robotics applications in health care are mentioned as examples for problem settings, in which interdisciplinary TA succeed in developing discipline-crossing argumentation chains.  相似文献   
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