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61.
This study evaluates a wide range of machine learning techniques such as deep learning, boosting, and support vector regression to predict the collection rate of more than 65,000 defaulted consumer credits from the telecommunications sector that were bought by a German third-party company. Weighted performance measures were defined based on the value of exposure at default for comparing collection rate models. The approach proposed in this paper is useful for a third-party company in managing the risk of a portfolio of defaulted credit that it purchases. The main finding is that one of the machine learning models we investigate, the deep learning model, performs significantly better out-of-sample than all other methods that can be used by an acquirer of defaulted credits based on weighted-performance measures. By using unweighted performance measures, deep learning and boosting perform similarly. Moreover, we find that using a training set with a larger proportion of the dataset does not improve prediction accuracy significantly when deep learning is used. The general conclusion is that deep learning is a potentially performance-enhancing tool for credit risk management.  相似文献   
62.
More than 25 years after the German reunification, data show that products/brands from the eastern regions of Germany (“Neue Länder”) still do not have significant shares in the country's western part (“Alte Länder”). To analyze potential reasons for this phenomenon, our current study replicates a previous study that investigated selected attitudes of Alte Länder consumers toward products/brands from the Neue Länder. It is shown that factors such as consumer ethnocentrism, product judgment, willingness to buy, and economic animosity continue to influence consumer behavior and as such our study offers potential explanation for the failure of Neue Länder products/brands in the western regions of Germany.  相似文献   
63.
The use of the Internet is becoming increasingly integral to the day-to-day operations of society, facilitating an interconnected and globalised world, where geographic barriers are no longer a defining criteria for communication. This opens the researcher up to a realm of research opportunities, which to-date have been under-exploited. This paper contributes to the wider body of literature addressing the concept of Online research, demonstrating in practice how it can be utilised in the context of interpretative phenomenological analysis. It is argued that netnography is akin to interpretative phenomenological analysis (IPA) in that it accounts for an individual’s personal perception or account of an event or state, as opposed to attempting to produce an objective record. This paper outlines how blog analysis can be utilised in the context of IPA, demonstrating how this worked in practice during the initial exploratory research phase of the teaching English as a foreign language tourism phenomenon.  相似文献   
64.
Prior literature indicates that quadratic models and the Black–Karasinski model are very promising for CDS pricing. This paper extends these models and the Black [J. Finance 1995, 50, 1371–1376] model for pricing sovereign CDS’s. For all 10 sovereigns in the sample quadratic models best fit CDS spreads in-sample, and a four factor quadratic model can account for the joint effects on CDS spreads of default risk, default loss risk and liquidity risk with no restriction to factors correlation. Liquidity risk appears to affect sovereign CDS spreads. However, quadratic models tend to over-fit some CDS maturities at the expense of other maturities, while the BK model is particularly immune from this tendency. The Black model seems preferable because its out-of-sample performance in the time series dimension is the best.  相似文献   
65.
We study the cost of shocks, that is, jump risk, with respect to reserve management when the reserve process is formulated as a drift‐switching jump diffusion with a reflecting barrier at 0. Inspired by the Brownian drift switching model, our model results in a more realistic dynamic behavior of international reserves than the buffer stock model. The new model can capture both the jump behavior in reserve dynamics and the leptokurtic feature of the increment distribution which has a higher peak and two asymmetric heavier tails than the normal distribution. Through the selection of an initial distribution that reflects certain steady state behaviors, the reserve process becomes a regenerative process. This selection enables us to derive a closed‐form expression for the total expected discounted cost of managing reserves, thus helping us to numerically find management strategies that minimize costs. The numerical results show that shocks at the reserve level have a significant effect on reserve management strategies and that model misspecification can result in nonnegligible additional costs.  相似文献   
66.
Nowadays, interest in corporate environmental strategies shifts from cleaner processes to the holistic nature of green products. The relevant literature argues that firms have the opportunity to pioneer through green product innovation, allowing them to differentiate and thus gain competitive advantage. Environmental burden of products during their entire life cycle is undeniable. Due to the weakness of the existing literature that inadequately addresses a commonly accepted green product definition, as well as the thereby caused inconclusive academic empirical results on firms' competitiveness, there are many cases of businesses greenwashing behavior. The overall contribution of this exploratory paper, on determining and evaluating the degree of greenness of a product, is twofold; first, starting with a systematic literature review, authors further contribute by proposing an integrative definition that addresses the so far existing terminological gap. Next, after reviewing the existing environmental assessment tools, authors based on the developed definition and in accordance to its dynamic dimension contribute to the existing methodology, as the paper reveals issues that need to be considered in the evaluation of green products.  相似文献   
67.
We model market integration in the Middle East and Africa by analyzing price dispersion and testing the law of one price (LOP) on highly-comparable actual local retail prices of 135 goods and services across 23 countries in the region over the period of 1990–2016. Second-generation panel estimators are applied to four price benchmarks: Regional average, South Africa, China, and US prices. Cross-regional price dispersion diminishes considerably over time up to 2008, particularly for non-tradeables around China price. The test of LOP indicates the percentage of convergent prices is highest in China price benchmark, followed by US, South Africa, and regional average benchmarks. Direct estimation of the convergence speed confirms this order. Overall, the results show evidence of increasing market integration in Middle East and Africa but it appears to be driven by global forces and, especially, the rise of China as a new economic power. The results show that some emerging market economies, such as China, can step up and promote integration while traditional economic powerhouses, such as the USA and UK, disengage from international economic relations.  相似文献   
68.
随着我国社会发展的不断推进与创新,对于执政基础的巩固、在最大限度内保证党的执政能力等均成为使基层党建可以获得良好效果的主要手段,并且使工作在不断的实践探索中获得更好的成效。但是,以党建引领基层社会治理的过程仍然存在众多问题,其中包括形式化严重以及做表面功夫等。因此,如何在新时代的背景下,通过党的全面领导将党与群众紧密地联系在一起,从而确保党建工作可以在基层发挥更强的社会治理职能,已成为基层社会治理模式探索并创新的主要内容。  相似文献   
69.
Advocates of public‐private partnerships (PPPs) argue that they can deliver public infrastructure more efficiently than traditional procurement through timelier completion and superior value for money. Despite these claims comparative analysis of the performance of both procurement methods has received scant attention in the PPP literature to date. This paper addresses this issue by providing an in‐depth, case‐based comparison of PPP versus traditional procurement in the schools sector in Ireland. Through detailed semi‐structured interviews with key stakeholders and an examination of the available documentation, we assess whether the key objectives of using PPP have been achieved. Overall, we find no evidence that PPP leads to faster delivery of infrastructure when the overall procurement process from contract notice to delivery is accounted for. In addition, we find only limited evidence to suggest that PPP results in better value for money.  相似文献   
70.
The authors propose and empirically test a causal model to understand how the availability of fair-trade information and consumer knowledge about this issue affect consumers’ attitudes and intentions toward fair-trade products. The model is built upon the attitude-behavior paradigm and the premises of agency theory. It is tested through structural equation modeling with a sample of 292 Spanish consumers. The findings are that consumers do not have good knowledge about fair trade and that this is significantly determined by the lack of information about this in the market. It is also observed that consumers’ perceptions about the availability of fair-trade information have negative effects on their concern about this issue and that such information as is available is not effective in reducing consumer skepticism. The research represents an extension of previous fair-trade literature because the role of information and communication in improving consumer attitudes and buying intentions has rarely been explored in the case of ethical products.  相似文献   
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