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51.
R. Van de Ven  N. C. Weber 《Statistics》2013,47(3-4):345-352
Upper and lower bounds are obtained for the mean of the negative binomial distribution. These bounds are simple functions of a percentile determined by the shape parameter. The result is then used to obtain a robust estimate of the mean when the shape parameter is known.  相似文献   
52.
This short article shows an unified approach to representing and computing the cumulative distribution function for noncentral t, F, and χ2. Unlike the existing algorithms, which involve different expansion and/or recurrence, the new approach consistently represents all the three noncentral cumulative distribution functions as the integral of the normal cumulative distribution function and χ2 density function.  相似文献   
53.
Non-central chi-squared distribution plays a vital role in statistical testing procedures. Estimation of the non-centrality parameter provides valuable information for the power calculation of the associated test. We are interested in the statistical inference property of the non-centrality parameter estimate based on one observation (usually a summary statistic) from a truncated chi-squared distribution. This work is motivated by the application of the flexible two-stage design in case–control studies, where the sample size needed for the second stage of a two-stage study can be determined adaptively by the results of the first stage. We first study the moment estimate for the truncated distribution and prove its existence, uniqueness, and inadmissibility and convergence properties. We then define a new class of estimates that includes the moment estimate as a special case. Among this class of estimates, we recommend to use one member that outperforms the moment estimate in a wide range of scenarios. We also present two methods for constructing confidence intervals. Simulation studies are conducted to evaluate the performance of the proposed point and interval estimates.  相似文献   
54.
毛雪彦  张亚辉 《民族学刊》2015,6(4):8-16,95-97
古典进化论学派学者麦克伦南(John· Fergus· McLennan)曾在其著作《原始婚姻》中对一妻多夫这种婚姻家庭形态进行了论述。麦克仑南对一妻多夫的基本看法是,这种婚姻家庭形态并不是一种例外和反常形态,而认为一妻多夫是人类社会发展的一个重要和普遍阶段。麦克仑南的这个论点是基于他对人类早期社会基本图景的推论和分析。本文试图在说明麦克伦南关于人类早期社会与婚姻发展脉络的基础上,来讨论一妻多夫制在其中的序列与价值。  相似文献   
55.
Fernando Martins 《LABOUR》2015,29(3):291-309
This paper exploits the information collected from a survey conducted on a sample of Portuguese firms to study the patterns of firms’ price and wage adjustments and the extent of nominal price and wage rigidities. The evidence shows that the frequency of price changes varies substantially across sectors and depends on the intensity of competition, the share of labor costs and firms’ price reviewing behavior. The results also suggest that the constraint imposed by the presence of downward nominal wage rigidity is less important in firms where the fraction of permanent and high‐skilled workers is lower and the share of flexible pay components is higher.  相似文献   
56.
Using data on Members of the European Parliament (MEPs), we examine the impact of salaries on the composition and the behavior of legislators. Employing a differences‐in‐differences approach, we exploit the introduction of a law that equalized MEPs' salaries which had previously differed by as much as a factor of 10. Increasing salaries raises the fraction of MEPs who run for re‐election but decreases the quality of elected MEPs (proxied by college quality). Salary has no discernible impact on effort or legislation output. Higher salaries induce more political competition.  相似文献   
57.
The recent period of capital outflows from emerging economies has coincided with an increase in their corporate saving. In this paper, we model corporate saving as a demand for liquid assets by credit‐constrained firms in a dynamic open‐economy macroeconomic model. We find that the implications of this model are very different from standard models, because the demand for foreign bonds is a complement to domestic investment rather than a substitute. We show that this complementarity is at work when an emerging economy is on its convergence path or when it has a higher TFP growth rate. This framework is consistent with a number of stylized facts found in high‐growth, high‐investment emerging economies.  相似文献   
58.
We measure the relative ideological positions of newspapers, voters, interest groups, and political parties, using data on ballot propositions. We exploit the fact that newspapers, parties, and interest groups take positions on these propositions, and the fact that citizens ultimately vote on them. We find that, on average, newspapers in the United States are located almost exactly at the median voter in their states—that is, they are balanced around the median voter. Still, there is a significant amount of ideological heterogeneity across newspapers, which is smaller than the one found for interest groups. However, when we group propositions by issue area, we find a sizable amount of ideological imbalance: broadly speaking, newspapers are to the left of the state‐level median voter on many social issues, and to the right on many economic issues. To complete the picture, we use two existing methods of measuring bias and show that the news and editorial sections of newspapers have almost identical partisan positions.  相似文献   
59.
Rising healthcare costs have sparked debate about the best way to provide high‐quality affordable health insurance. We discuss the potential for regulated insurance markets to outperform single‐payer public insurance. We use as an example the private Medicare plans that now provide insurance to almost a third of seniors in the United States. The evidence suggests that private plans can limit costs and potentially appeal to enrollees, and that well‐designed risk adjustment can mitigate market failures due to adverse selection. However, fostering competition between insurers, especially in smaller markets, is difficult. We discuss how future research might illuminate the relative advantages of public and private health insurance.  相似文献   
60.
王兴棠  李杰 《管理科学》2020,23(9):61-75
随着全球化程度加深,与国外企业进行研发合作逐步成为国内企业参与创新驱动发展战略的重要途径.从中间品贸易视角出发,通过构建谈判博弈模型,分析探讨影响产业链下游企业进行国际研发合作内生性选择的因素.研究发现,只有在研发溢出效应比较小的时候,产业链下游企业才会选择进行国际研发合作.但如果研发溢出效应过小,下游企业的国际研发合作行为会导致本国社会福利水平下降.进一步研究发现,上游市场垄断势力增强以及最终品贸易成本下降均会对产业链下游企业的国际研发合作产生促进作用.  相似文献   
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