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91.
92.
Erik Koenen 《Publizistik》2018,63(4):535-556
In the discussion about the future of communication and media science in digital times, this article focuses on the position and perspective of communication and media history. The challenges, problems and potentials associated with digitization are illustrated using the example of historical press research. Within the media ensemble of classical mass communication, the periodic press in particular benefits from the retrospective digitization of historical media and their digital edition in databases and portals. For historical press research, digitized newspapers and digital newspaper portals represent an originally new, because increasingly digital research situation: Digital newspaper portals as a novel, originally digital world for newspapers not only facilitate the path to newspapers and their contents, they also open them up as digital resources machine-readable and thus open up completely new paths for research—not least supported by digital methods.The main objective of this article is to discuss the epistemological-methodological problems and the practical operationalization of digitally framed or supported research processes in historical press research and to present concrete perspectives of knowledge and research strategies for practice. With this aim in mind, the paper discusses three points:(1.) Methodological and practical consequences of historical press research in digital research environments. With the digitization of newspapers and their digital reproduction in newspaper portals, their source character shifts essentially in three dimensions: They are edited and indexed digitally and their complete content is made accessible through optical character recognition. This makes previously unimportant technical aspects such as data formats, portal interfaces, search algorithms and programming interfaces very relevant for the methodology of historical press research. A primary methodological effect of the digital reorganization of newspapers in data and portals is the reversal of the usual reading practice: from “top down” to “bottom up”. With the help of “keyword searching”, newspapers can now be searched comprehensively and transversely to the order of the newspaper original. Nevertheless, there is a warning against an all too naïve and uncritical usage of digitized newspapers and newspaper portals. In practice, some problems and risks are crucial for the conception of historical newspaper research in digital research environments: Besides a hardly standardized and in large parts “wild”, because often uncoordinated and selective digitization of newspapers, the newspaper portals are different in their conception as well as characterized by different content, technical, legal and entrepreneurial conditions.(2.) Historical newspapers as digital sources in practice. The methodological and technical framework are fundamental and far-reaching for the further practical use of newspapers as digital sources in research. In each research step, it must be considered that digitized newspapers are genuinely new and, depending on the quality and depth of digitization, very complex sources with information gains and losses compared to the originals. Newspapers are not simply digitized, they are digitally constructed and differ in this construction from each other. In this respect, historical press researchers are increasingly becoming “users”. However simple and uncomplicated newspaper portals may be in practice, one must incorporate the implicit functions (hidden in algorithms, data and code) and the limits of these knowledge engines and their “correct” use into the research process. Combining and mediating classical hermeneutic methods with search technologies is an essential moment in the practical handling of digitized newspapers.(3.) Historical press research and digital methods. In the light of the new research situation which is emerging with digitized newspapers and newspaper portals, it is obvious that historical press research should increasingly open up to the possibilities of digital methods. In the digital method discussion of historical press research, one concept in particular forms a central point of reference: Franco Moretti’s concept of “Distant Reading”. Basically, “Distant Reading”—and this is what makes this perspective so interesting for historical press research in dealing with the considerable metadata and full text volumes of digitized newspapers—is about the quantitative-automatic indexing of large text corpora using methods and techniques of “Text Mining”. Digital text methods are thus seriously changing the way we look at texts and the research practice with texts such as newspapers: In parts, they automate and accelerate reading processes, produce “new” text extracts by the computer, generate new interpretation contexts between individual text, corpus and condensate, and thus set new orientation points for “close reading”. Computers and digital text methods thus do not relieve researchers of interpretation. Rather, they constantly challenge them to interpret in a continuous interplay in order to give meaning to the text patterns discovered by machines.In spite of all these advantages, digital methods have so far only been used sporadically in historical press research. For this reason, finally a digital workflow for research processes in historical press research will be presented, which illustrates and summarizes essential challenges, problems, solutions and potentials of digitally framed or supported research in press history. 相似文献
93.
Cullen F. Goenner 《Review of Quantitative Finance and Accounting》2018,50(4):1227-1251
Beginning in 2011, credit unions in the United States have been required to report in their quarterly call reports their holdings of private student loans. Since this time, private student loans have been the fastest growing loan product among credit unions. The empirical results here indicate credit unions respond to external market forces and internal exposure to interest rate risk in their decision to hold private student loans. The effect of which, to date, has led to lower returns on their assets and no effect on overall risk. Credit unions looking to diversify their loan portfolio should do so with caution. Private student loans being in deferral reduce both delinquency and charge-off rates, which will rise over time with their seasoning and as interest rates rise. 相似文献
94.
We study the merits of capped retirement products with guarantee for investors who have the flexibility to dynamically adjust their investment strategy. All contracts under consideration are fairly priced such that the net profit of the provider is zero. Without the rider, an expected utility maximizing CRRA investor does not want an investment cap. Here, she commits herself to a strategy a priori. With the flexibility rider, the optimization problem changes and the optimal strategy is a response to an exogenously set price. A fair pricing then anticipates the optimal response of the investor. We show that the maximum expected utility of the investor can, for anticipated fairly priced products, be obtained for a finite cap. Thus, a capped product design can give a Pareto improvement to the otherwise uncapped contract version. 相似文献
95.
Dieter Farny 《保险科学杂志》2010,99(3):259-275
The Criterions of insurance companies in Germany are changing as consequences of market competition and regulation. Trends of differentiation follow former trends of assimilation. A modern typology of direct insurers resp. groups of insurers is less oriented by legal form of companies, more by targets of activities and stakeholder situation. In case of mutual companies there are effects of demutualization. 相似文献
96.
Jacco J. J. Thijssen 《Annals of Finance》2010,6(3):295-315
This paper presents a unified approach to valuing investment projects under uncertainty, based on stochastic discount factors,
by linking optimal stopping theory to the no-arbitrage principle in asset pricing. An investment threshold for the case where
the discount factor and the project’s cash-flow both follow a geometric Brownian motion is derived. Comparative statics of
the investment trigger are obtained adding to and clarifying on the uncertainty–investment debate. Finally, two different
ways to obtain discount factors are illustrated: spanning assets and representative agent analysis. The link between the characteristics
of these different approaches and the optimal investment policy is clarified. 相似文献
97.
Marie-Louise Leroux 《International Tax and Public Finance》2011,18(1):56-73
This paper studies a problem of non-linear taxation when individuals have different longevities resulting from a non-monetary effort (like exercising). We first present the laissez-faire and the first best. Like Becker and Philipson (J. Polit. Econ. 106(3):551–573, 1998), we find that the laissez-faire level of effort is too high compared with the first best, because individuals do not internalize the impact of survival on the return of their savings. We also claim that because of its non-monetary form, effort is not contractible. That is why we modify our framework and assume, for the rest of the paper, that effort is determined by the individual while the social planner only allocates consumptions. It turns out that, under full information, a tax on the return of annuitized savings is desirable for both types. This tax is higher for the low-survival individual. Under asymmetric information, the low-survival individual still faces a tax while the high-survival individual might now face a positive or negative tax on annuities. Interestingly, our results depend on the value of life. 相似文献
98.
The self-disclosure of individual-level consumer information for direct marketing purposes, such as interests, opinions, beliefs, competitor spending habits and future purchase intentions, is voluntary in nature. This raises the prospect that such information may be to some extent incomplete and unreliable. However, the availability, completeness and reliability of voluntarily disclosed personal information for direct marketing purposes has received little attention in the literature. This represents an important omission because all modern personalised targeting models such as neural networks, and all customer profiling and data appending practices, typically incorporate voluntarily disclosed individual-level information. Accordingly, the ability of the direct marketing industry to gather and use such information will exercise an increasingly prominent role in sustaining and extending its competitive position. Using 256 personal interviews and a case study, this paper quantifies typical levels of abstention from personal information disclosure, and omission and falsification of such disclosures, and considers the implications for direct marketing practice. 相似文献
99.
In the spirit of methodology reviews for stock event studies, like the one prepared by Binder (Rev Quant Financ Account 11:111–137, 1998), this paper discusses the development of the event study methodology for corporate bonds since its first application with Katz (J Financ 29:551–559, 1974). The motivation to conduct this review stems from two sources: First, the methodology utilized for stocks cannot simply be applied to bonds, as bonds present several features that strongly distinguish them from stocks. An erroneous model could lead to false conclusions about the impact of new information on a firm’s debt. Second, the availability of new sources for bond data enables the application of bond event studies for an increasing number of research frameworks. Thus, future research ought to be interested in the selection of the proper methodology. Consequently, this paper illustrates past and present event study methods utilized to calculate abnormal bond returns and reviews the applied parametric and non-parametric test statistics. Besides, insight on how the availability of corporate bond data has evolved through the last four decades, as well as the impact on prevailing methodology is provided. Altogether, this paper provides a first extensive snapshot of the current bond event study methodology and offers guidance for future research. 相似文献
100.
In many situations, governments have sector-specific tax and regulation policies at their disposal to influence the market
outcome after a national or an international merger has taken place. In this paper we study the implications for merger policy
when countries non-cooperatively deploy production-based taxes and firms may be partly owned by foreigners. We find that when
foreign firm ownership is low in the pre-merger situation, non-cooperative tax policies are more efficient after a national
merger, and smaller synergy effects are needed for this type of merger to be proposed and cleared. In contrast, cross-border
mergers dominate when the degree of foreign firm ownership is high initially. These results suggest a link between increasing
international portfolio diversification and the rising share of cross-border mergers. 相似文献