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1.
严文龙等 《统计研究》2020,37(7):93-103
在经济下行压力加大、资本市场进一步开放的新形势下,厘清审计市场交易——监管机制,完善审计服务市场尤为必要。借由2010 年审计定价管制政策失效的自然实验,本文通过嵌入双边随机边界模型,得到审计双方的定价交易剩余指标,运用双重差分模型解析价格管制与交易定价的作用机制。研究发现,定价管制失效的原因不在于规制俘获,而在于价格管制与当前的市场效率不匹配。下限管制尽管能够提高审计师剩余,但同时会放大交易定价风险,增加剩余的错配,扰乱交易秩序。上限管制则进一步固化市场的低价竞争。进一步研究发现审计师剩余与盈余质量显著相关,2014年的放开定价管制政策提高了审计师剩余。研究厘清了审计市场交易机制,有利于未来研究审计交易机制的微观影响及与盈余质量的关联,为在新时代把握审计市场交易——监管规律、培育自发良性交易的审计市场提供有益借鉴。  相似文献   
2.
20世纪20年代初期中苏建交谈判期间,苏俄从其自身国家安全利益出发,采取强行出兵外蒙追剿白匪和坚持长期驻军库伦的作法,来占有当时主权属于中国的外蒙古地区,在外蒙古问题上对华采取了大国沙文主义和民族利己主义政策.  相似文献   
3.
列宁逝世以后,布哈林继续坚持和捍卫列宁的新经济政策思想,并结合俄国的实际,针对当时苏联国民经济发展中出现的一系列问题,总结过去经济建设中的经验教训,系统地阐发自己的观点,从而形成了关于国民经济综合平衡发展的比较全面系统的理论。他认为,要使国民经济持续健康发展,必须尊重客观经济规律,重视市场调节的作用,使工业和农业、重工业和轻工业、农业内部、积累和消费之间保持综合平衡。在建设有中国特色社会主义的今天,重温布哈林的国民经济综合平衡发展理论,无疑会给我们以很好的教益和启迪。  相似文献   
4.
李彬 《南都学坛》2002,22(5):14-18
1921年白俄恩琴率军侵入外蒙古,从而引发国内直奉两系军阀一系列的矛盾斗争,使得当时的北洋政府坐失收复外蒙良机,最终导致外蒙从中国分裂出去,进而揭示出北洋军阀置国家疆土于不顾而忙于内争的实质。  相似文献   
5.
Parameter design or robust parameter design (RPD) is an engineering methodology intended as a cost-effective approach for improving the quality of products and processes. The goal of parameter design is to choose the levels of the control variables that optimize a defined quality characteristic. An essential component of RPD involves the assumption of well estimated models for the process mean and variance. Traditionally, the modeling of the mean and variance has been done parametrically. It is often the case, particularly when modeling the variance, that nonparametric techniques are more appropriate due to the nature of the curvature in the underlying function. Most response surface experiments involve sparse data. In sparse data situations with unusual curvature in the underlying function, nonparametric techniques often result in estimates with problematic variation whereas their parametric counterparts may result in estimates with problematic bias. We propose the use of semi-parametric modeling within the robust design setting, combining parametric and nonparametric functions to improve the quality of both mean and variance model estimation. The proposed method will be illustrated with an example and simulations.  相似文献   
6.
Many economic duration variables are often available only up to intervals, and not up to exact points. However, continuous time duration models are conceptually superior to discrete ones. Hence, in duration analyses, one faces a situation with discrete data and a continuous model. This paper discusses (i) the asymptotic bias of a conventional approximation procedure in which a discrete duration is treated as an exact observation; and (ii) the efficiency of a correct maximum likelihood estimator which appropriately accounts for the discrete nature of the data.  相似文献   
7.
Summary. The paper develops methods for the design of experiments for mechanistic models when the response must be transformed to achieve symmetry and constant variance. The power transformation that is used is partially justified by a rule in analytical chemistry. Because of the nature of the relationship between the response and the mechanistic model, it is necessary to transform both sides of the model. Expressions are given for the parameter sensitivities in the transformed model and examples are given of optimum designs, not only for single-response models, but also for experiments in which multivariate responses are measured and for experiments in which the model is defined by a set of differential equations which cannot be solved analytically. The extension to designs for checking models is discussed.  相似文献   
8.
Detection and correction of artificial shifts in climate series   总被引:6,自引:0,他引:6  
Summary.  Many long instrumental climate records are available and might provide useful information in climate research. These series are usually affected by artificial shifts, due to changes in the conditions of measurement and various kinds of spurious data. A comparison with surrounding weather-stations by means of a suitable two-factor model allows us to check the reliability of the series. An adapted penalized log-likelihood procedure is used to detect an unknown number of breaks and outliers. An example concerning temperature series from France confirms that a systematic comparison of the series together is valuable and allows us to correct the data even when no reliable series can be taken as a reference.  相似文献   
9.
Abstract. The use of the concept of ‘direct’ versus ‘indirect’ causal effects is common, not only in statistics but also in many areas of social and economic sciences. The related terms of ‘biomarkers’ and ‘surrogates’ are common in pharmacological and biomedical sciences. Sometimes this concept is represented by graphical displays of various kinds. The view here is that there is a great deal of imprecise discussion surrounding this topic and, moreover, that the most straightforward way to clarify the situation is by using potential outcomes to define causal effects. In particular, I suggest that the use of principal stratification is key to understanding the meaning of direct and indirect causal effects. A current study of anthrax vaccine will be used to illustrate ideas.  相似文献   
10.
本文总结了高能核—核碰撞的多源模型自1987年提出到1990年以来的主要进展,着重介绍多源模型的基本物理思想及其在两种不同方案下的发展动态.通过与最新实验数据比较,说明多源模型能够成功地解释高能重离子碰撞的整体性质.  相似文献   
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