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1.
许瑾  刘炫均  冯冠钦 《科技和产业》2021,21(10):302-308
随着电力变压器朝着大容量、高电压、高负荷的方向发展,其结构也越发复杂,故障逐渐增加.当前广泛使用的改良三比值法在对电力变压器进行故障诊断的过程中,容易出现准确率低和漏判率高等问题.鉴于此,提出一种NBC模型,该模型将朴素贝叶斯网络和改良三比值法的优势结合,在对电力变压器当前状态数据和历史样本数据充分学习的基础上,利用朴素贝叶斯分类器对当前电力变压器故障的编码组合进行故障预测分类,将预测所得到的诊断结果进行排序整理输出,实现了对电力变压器各类故障的有效分类.仿真结果表明,该NBC模型能较好地适应电力变压器各类故障的诊断,故障综合诊断正确率为95%,相较于改良三比值法,诊断准确率提升了50%,具有较强的工程实用性.  相似文献   
2.
仿制药专利挑战机制是我国药品专利链接制度的核心环节。在现有规范体系下进行制度构建,存在同现行《专利法》抵触的问题,通过立法或释法活动化解这种冲突具有必要性。在解释学范式下对仿制药品专利挑战侵权拟制、侵权解释两种立法进路进行推演和反思,并辅之以制度体系、国际比较、法律政策、经济分析等视角,可得出拟制进路更为可行的结论。在拟制进路下进行制度构建,应遵循法律拟制技术规范,并妥善处理制度配套问题。  相似文献   
3.
New product activity is critical for sustained success of consumer packaged goods (CPG) brands. However, the impact of new SKUs on the perceived quality, quality uncertainty and subsequent choice of the brand as a whole is, as of yet, not well understood. The authors study how new additions to the brand line shape consumers’ quality perceptions, and how this – next to the mere line length effect – influences their choice of brands over time. They do so in the setting of an emerging market (China), where new product activity is particularly pervasive. Using a unique scanner panel dataset of Chinese households over the period 2011–2014, they estimate a Bayesian learning model that accommodates varying quality, on two CPG categories, and for two types of new-product additions (new sensory SKUs vs. new non-sensory SKUs). They show that while adding new SKUs may lift the brand’s perceived quality level, it also makes consumers more uncertain about the quality of the brand – dampening their brand choice. This holds especially for light customers – an important part of the brand clientele. Managerial implications are discussed.  相似文献   
4.
Monetary policy in the United States has been documented to have switched from reacting weakly to inflation fluctuations during the 1970s, to fighting inflation aggressively from the early 1980s onward. In this paper, I analyze the impact of the U.S. monetary policy regime switches on the Eurozone. I construct a New Keynesian two‐country model where foreign (U.S.) monetary policy switches regimes over time. I estimate the model for the U.S. and the Euro Area using quarterly data and find that the United States has switched between those two regimes, in line with existing evidence. I show that foreign regime switches affect home (Eurozone) inflation and output volatility and their responses to shocks, substantially, as long as the home central bank commits to a time‐invariant interest rate rule reacting to domestic conditions only. Optimal policy in the home country instead requires that the home central bank reacts strongly to domestic producer‐price inflation and to international variables, such as imported goods relative prices. In fact, I show that currency misalignments and relative prices play a crucial role in the transmission of foreign monetary policy regime switches internationally. Interestingly, I show that only marginal gains arise for the Euro Area when the European Central Bank (ECB) adjusts its policy according to the monetary regime in the United States. Thus, a simple time‐invariant monetary policy rule with a strong reaction to Producer Price Index (PPI) inflation and relative prices is enough to counteract the effects of monetary policy switches in the United States.  相似文献   
5.
This paper proposes a new framework for the estimation of product-level global and interregional feedback and spillover (FS) factor multipliers. The framework is directly based on interregional supply and use tables (SUTs) that could be rectangular and gives a possibility of taking account of the inherent input–output data uncertainty problems. A Bayesian econometric approach is applied to the framework using the first version of international SUTs in the World Input–Output Database. The obtained estimates of the global and intercountry FS output effects are discussed and presented at the world, country and product levels for the period of 1995–2009.  相似文献   
6.
7.
Abstract

This paper measures the degree of bank competition in India using a sample of 70 commercial banks over the period 1996–2016. To assess the degree of competition, we estimate the market power of each bank in our sample employing three nonstructural measures: the Lerner index, the adjusted Lerner index, and the Boone indicator. Bank-wise and year-wise estimates of the marginal cost required in all these measures are obtained using the semi-parametric method. The paper further attempts to undertake a comprehensive assessment of competition in Indian banking and identifies various bank-specific, macroeconomic, structural, and contestability indicators, which are supposed to explain level and variation of the degree of competition over time. Empirical findings reveal that public-sector banks in India exercise a relatively higher degree of bank competition compared to private and foreign-sector banks. However, aggregate results support that the Indian banking system is competitive in general. Unlike the structure-conduct-performance paradigm, which advocates that a concentrated banking system impairs competitiveness, our findings reveal that concentration measures hardly exert any effect on bank competition. Rather, contestability measures play a significant role in the determination of bank competition.  相似文献   
8.
We study the behaviours of the Betfair betting market and the sterling/dollar exchange rate (futures price) during 24 June 2016, the night of the EU referendum. We investigate how the two markets responded to the announcement of the voting results by employing a Bayesian updating methodology to update prior opinion about the likelihood of the final outcome of the vote. We then relate the voting model to the real-time evolution of the market-determined prices as the results were announced. We find that, although both markets appear to be inefficient in absorbing the new information contained in the vote outcomes, the betting market seems less inefficient than the FX market. The different rates of convergence to the fundamental value between the two markets lead to highly profitable arbitrage opportunities.  相似文献   
9.
Spatial models, such as the Besag, York and Mollie (BYM) model, have long been used in epidemiology and disease mapping. A common research question in these subjects is modelling the number of disease events per region; here the BYM models provides a holistic framework for both covariates and dependencies between regions. We use these tools to assess the relative insurance risk associated with the policyholders geographical location. A Bayesian modelling approach is presented and an elastic net is used to reduce the large number of possible geographic covariates. The final inference is performed using Integrated Nested Laplace Approximation. The model is applied to car insurance data from If P&C Insurance together with spatially referenced covariate data of high resolution, provided by Insightone. The entire analysis is performed using freely available R-packages. Including spatial dependence when modelling the number of claims significantly improves on the result obtained using ordinary generalised linear models. However, the support for adding a spatial component to the model for claims cost is weaker.  相似文献   
10.
We estimate a Bayesian VAR (BVAR) for the UK economy and assess its performance in forecasting GDP growth and CPI inflation in real time relative to forecasts from COMPASS, the Bank of England’s DSGE model, and other benchmarks. We find that the BVAR outperformed COMPASS when forecasting both GDP and its expenditure components. In contrast, their performances when forecasting CPI were similar. We also find that the BVAR density forecasts outperformed those of COMPASS, despite under-predicting inflation at most forecast horizons. Both models over-predicted GDP growth at all forecast horizons, but the issue was less pronounced in the BVAR. The BVAR’s point and density forecast performances are also comparable to those of a Bank of England in-house statistical suite for both GDP and CPI inflation, as well as to the official Inflation Report projections. Our results are broadly consistent with the findings of similar studies for other advanced economies.  相似文献   
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