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1.
This article presents a new approach to modeling information flows within today's information systems environments characterized by electronic commerce. We treat information as a resource whose value is fundamentally multidimensional in nature. In this article we consider the economic and psychological dimensions of the value of information. It is argued that it is meaningless to model the value of information in isolation away from the context and the specific parties between which this information is exchanged. We therefore focus exclusively on modeling information flows rather than information itself. To achieve this, we propose a formal framework for describing transactions involving information flows. The framework consists of a generalized model for representing information transactions and for defining a set of fundamental properties of multiparty transactions. These properties are fairness, constructiveness, and monopoly. Where applicable, they are defined for individuals, transactions, and a system of transactions. The proposed model reveals the nature of individual transactions and markets, and consequently has important implications for simulation of market scenarios and to help arrive at effective policies for pricing and market regulations.  相似文献   

2.
判别国际资本市场波动时我国的冲击路径,防范国际金融风险冲击是维护国家金融安全的重要前提.国际资本流动、信息跨境传递以及投资者情绪的相互影响均可能在国家间传导金融风险.本文运用多元GARCH模型(BEKK)实证检验了美国资本市场波动和人民币汇率变化对我国资本市场的冲击传导关系,进而判别国际资本流动是否会对我国资本市场形成冲击.实证结论表明:汇率市场的风险波动程度显著低于资本市场,且美国资本市场与人民币汇率、我国资本市场与人民币汇率均存在显著的双向“风险溢出”效应.由此可以推断,国际资本市场风险通过国际资本流动的途径对我国市场形成冲击的事实.  相似文献   

3.
Language modeling is an effective and theoretically attractive probabilistic framework for text information retrieval. The basic idea of this approach is to estimate a language model of a given document (or document set), and then do retrieval or classification based on this model. A common language modeling approach assumes the data D is generated from a mixture of several language models. The core problem is to find the maximum likelihood estimation of one language model mixture, given the fixed mixture weights and the other language model mixture. The EM algorithm is usually used to find the solution.  相似文献   

4.
基于Bertrand模型的关系型借贷和中小企业融资研究   总被引:2,自引:0,他引:2  
信息不透明、缺乏与融资有关的有效信息、融资成本高是中小企业融资难的主要原因,关系型借贷实质上是银行和企业为克服金融交易中的市场失效而共同构建的一种制度安排.本文基于Bertrand成本控制的竞争框架,通过一个理论模型分析关系型借贷和银行的定价行为.研究表明即使借主与银行存在长期的关系.缺乏有效的融资信息迫使中小企业承担高贷款利率.同时从理论上解释中小企业经常面临借贷限制的原因.  相似文献   

5.
针对现代信息服务产业集群发展存在的信息共享不足、信息流动不畅、协同机制缺乏等问题,从信息生态系统的视角考察其协同运营的机制与商业模式,以强化现代信息服务产业集群中的信息人、信息环境的整合、互动、共享和协同等机制为基础,构建一种基于信息生态系统观的现代信息服务产业集群协同创新发展模式的基本框架。这种以信息流为中心,将资金流、物流、业务流、价值流等集成一体化的协同模式,有利于提高这一产业集群中信息与知识的共享、开发与利用效能,强化价值创造、实现和共享的意愿和能力。通过实例表明,此模式为现代信息服务业的一体化协同创新发展提供了一种新的、可资借鉴的参考模式与实现途径,从而促进现代信息服务产业集群的健康可持续发展。  相似文献   

6.
《普罗米修斯》2012,30(3):193-209

In studies of firms' internationalisation, language has tended to be bundled into 'cultural and psychic distance boxes'. In this article, an attempt is made to unbundle the impact of language through (a) an examination of the way in which language influences the pattern of foreign market expansion; and (b) an analysis of how a firm may try to cope with language diversity by adopting a common corporate language. We conclude that attempts to impose a common corporate language may hinder or alter information flows, knowledge transfer, and communication.  相似文献   

7.
8.
Fairness is fundamental to all information access systems, including recommender systems. However, the landscape of fairness definition and measurement is quite scattered with many competing definitions that are partial and often incompatible. There is much work focusing on specific – and different – notions of fairness and there exist dozens of metrics of fairness in the literature, many of them redundant and most of them incompatible. In contrast, to our knowledge, there is no formal framework that covers all possible variants of fairness and allows developers to choose the most appropriate variant depending on the particular scenario. In this paper, we aim to define a general, flexible, and parameterizable framework that covers a whole range of fairness evaluation possibilities. Instead of modeling the metrics based on an abstract definition of fairness, the distinctive feature of this study compared to the current state of the art is that we start from the metrics applied in the literature to obtain a unified model by generalization. The framework is grounded on a general work hypothesis: interpreting the space of users and items as a probabilistic sample space, two fundamental measures in information theory (Kullback–Leibler Divergence and Mutual Information) can capture the majority of possible scenarios for measuring fairness on recommender system outputs. In addition, earlier research on fairness in recommender systems could be viewed as single-sided, trying to optimize some form of equity across either user groups or provider/procurer groups, without considering the user/item space in conjunction, thereby overlooking/disregarding the interplay between user and item groups. Instead, our framework includes the notion of statistical independence between user and item groups. We finally validate our approach experimentally on both synthetic and real data according to a wide range of state-of-the-art recommendation algorithms and real-world data sets, showing that with our framework we can measure fairness in a general, uniform, and meaningful way.  相似文献   

9.
To explore the relationship of information capital and company performance as mediated by business processes, we sought to establish an analytical framework based on knowledge based view for international trade companies to better develop the innovative capacity of holistic thinking processes of domestic trade enterprises. Using structural equation modeling as part of an analytical research framework, we found that information capital can indirectly affect company performance when mediated by business processes, and that information capital is more critical to the trade industry. This finding reveals that adopting and assimilating information systems form an important channel for companies to provide strategic information and use information capital. We highlighted that the improvement of information capital can significantly enhance a company’s competitiveness and that, since business processes play key mediating roles, the timely adjustment of such processes can allow information capital to enhance company performance of the international trade industry.  相似文献   

10.
Efficient management of toxicity information as an enterprise asset is increasingly important for the chemical, pharmaceutical, cosmetics and food industries. Many organisations focus on better information organisation and reuse, in an attempt to reduce the costs of testing and manufacturing in the product development phase. Toxicity information is extracted not only from toxicity data but also from predictive models. Accurate and appropriately shared models can bring a number of benefits if we are able to make effective use of existing expertise. Although usage of existing models may provide high-impact insights into the relationships between chemical attributes and specific toxicological effects, they can also be a source of risk for incorrect decisions. Thus, there is a need to provide a framework for efficient model management. To address this gap, this paper introduces a concept of model governance, that is based upon data governance principles. We extend the data governance processes by adding procedures that allow the evaluation of model use and governance for enterprise purposes. The core aspect of model governance is model representation. We propose six rules that form the basis of a model representation schema, called Minimum Information About a QSAR Model Representation (MIAQMR). As a proof-of-concept of our model governance framework we develop a web application called Model and Data Farm (MADFARM), in which models are described by the MIAQMR-ML markup language.  相似文献   

11.
This paper is part of a series examining the fundamental nature of informatics: a term used as a convenient umbrella term to stand for the overlapping disciplinary areas of information systems, information management and information technology. The aim of the current paper is to consider some of the universal features of information technology. This is accomplished in terms of a conceptual framework established in previous work. We ground the discussion in a significant historical case: that of Hollerith's electric tabulating system which constituted one of the earliest examples of automatic data processing. Through examination of this case and the technologies used we establish an interpretation of the essence of information technology in terms of formative acts of data representation and processing.  相似文献   

12.
The estimation of query model is an important task in language modeling (LM) approaches to information retrieval (IR). The ideal estimation is expected to be not only effective in terms of high mean retrieval performance over all queries, but also stable in terms of low variance of retrieval performance across different queries. In practice, however, improving effectiveness can sacrifice stability, and vice versa. In this paper, we propose to study this tradeoff from a new perspective, i.e., the bias–variance tradeoff, which is a fundamental theory in statistics. We formulate the notion of bias–variance regarding retrieval performance and estimation quality of query models. We then investigate several estimated query models, by analyzing when and why the bias–variance tradeoff will occur, and how the bias and variance can be reduced simultaneously. A series of experiments on four TREC collections have been conducted to systematically evaluate our bias–variance analysis. Our approach and results will potentially form an analysis framework and a novel evaluation strategy for query language modeling.  相似文献   

13.
The Digital Divide as a Complex and Dynamic Phenomenon   总被引:9,自引:0,他引:9  
The purpose of this article is to propose a fruitful analytical framework for data supposedly related to the concept of the so-called "digital divide." The extent and the nature of this divide depend on the kind of access defined. Considering the possession of hardware, growing divides among different categories of income, employment, education, age, and ethnicity can be proved to have existed in the 1980s and 1990s according to official American and Dutch statistics. If only by effects of saturation, these gaps will more or less close. However, it is shown that differential access of skills and usage is likely to increase. The growth of a usage gap is projected. Multivariate analyses of Dutch official statistics reveal the striking effect of age and gender as compared to education. The usage gap is related to the evolution of the information and network society. Finally, policy perspectives are discussed.  相似文献   

14.
Platform-based customer agility is the ability to leverage the voice of the customer on a platform to achieve market intelligence and to explore competitive action opportunities. Prior studies have indicated the critical role of customer agility in enabling the survival and prosperity of contemporary organizations in a turbulent business environment, although how to develop this capability is not answered. The current research attempts to fill this theoretical gap. Drawing on the information management literature, we propose an integrative information management framework to investigate the process of developing customer agility. By conducting a case study of a leading e-commerce platform in China, we identify three types of platform-based customer agility (i.e. reactive customer agility, proactive customer agility, and coactive customer agility) in different phases of the growth of the platform. Furthermore, a process model is developed from the case study. It shows that platform-based customer agility is achieved by establishing information management structure, developing information management capability, and instilling information management culture. This study contributes to the knowledge on customer agility and information management. Detailed recommendations are also provided for potential practitioners.  相似文献   

15.
The purpose of this article is to propose a fruitful analytical framework for data supposedly related to the concept of the so-called "digital divide." The extent and the nature of this divide depend on the kind of access defined. Considering the possession of hardware, growing divides among different categories of income, employment, education, age, and ethnicity can be proved to have existed in the 1980s and 1990s according to official American and Dutch statistics. If only by effects of saturation, these gaps will more or less close. However, it is shown that differential access of skills and usage is likely to increase. The growth of a usage gap is projected. Multivariate analyses of Dutch official statistics reveal the striking effect of age and gender as compared to education. The usage gap is related to the evolution of the information and network society. Finally, policy perspectives are discussed.  相似文献   

16.
Language modeling (LM), providing a principled mechanism to associate quantitative scores to sequences of words or tokens, has long been an interesting yet challenging problem in the field of speech and language processing. The n-gram model is still the predominant method, while a number of disparate LM methods, exploring either lexical co-occurrence or topic cues, have been developed to complement the n-gram model with some success. In this paper, we explore a novel language modeling framework built on top of the notion of relevance for speech recognition, where the relationship between a search history and the word being predicted is discovered through different granularities of semantic context for relevance modeling. Empirical experiments on a large vocabulary continuous speech recognition (LVCSR) task seem to demonstrate that the various language models deduced from our framework are very comparable to existing language models both in terms of perplexity and recognition error rate reductions.  相似文献   

17.
Despite the many implicit references to the social contexts of search within information seeking and retrieval research, there has been relatively little work that has specifically investigated the additional requirements for collaborative information-seeking interfaces. Here, we re-assess an existing analytical inspection framework, designed for individual information seeking, and then apply it to evaluate a recent collaborative information-seeking interface: SearchTogether. The framework was built upon two models of solitary information seeking, and so as part of the re-assessment we first re-frame the models for collaborative contexts. We re-frame a model of search tactics, providing revised definitions that consider known collaborators. We then re-frame a model of searcher profiles to analyse support for different group dynamics. After presenting an analysis of SearchTogether, we reflect on its accuracy, showing that the framework identified eight known truths, eight new insights, and no known-to-be-untrue insights into the design. We conclude that the framework: (a) can still be applied to collaborative information-seeking interfaces; (b) can successfully produce additional requirements for collaborative information-seeking interfaces; and (c) can successfully model different dynamics of collaborating searchers.  相似文献   

18.
The lack of consensus on the meaning and role of decision support systems (DSSs), in the market and in academia, indicates that DSS as a field is not maturely defined and modeled. Moreover, an integrated view of the field is necessary to assess the role and value of DSS products and services. Such a view is also a prerequisite for understanding the issues of integration, as well as the potential contributions of artificial intelligence (AI) and expert systems (ES). This paper presents a unified and dynamic model showing the relationships of knowledge, information, decision, and action in the decision process. DSS modeling is viewed as a logical deduction of the utility (goal) structure. Using the framework of the model, the sequence and phases of decision making are revised. The concept of situation model is introduced. Four categories of information are addressed: instruction, historical, predicted value of alternatives, and patterns. The role of existing and potential support systems and their evolution toward utilization of ES and AI are discussed.  相似文献   

19.
In this paper, we investigate the relationship between location patterns, innovation processes and industrial clusters. In order to do this we extend a transactions costs-based classification into a knowledge-based taxonomy of clusters, along the lines suggested by a critical revision of the main assumptions underlying most of the existing literature on spatial clusters. Our arguments show that the transactions costs approach and the innovation and technological regimes framework are broadly consistent, and that real insights into the microfoundations, nature, and evolution of clusters can be provided by these classification systems.  相似文献   

20.
The valuation of patents is an important, albeit challenging task. Extant research to identify patent value indicators has so far relied on expert estimates of patent value, exploited patent renewal data, or depended on more indirect measures of patent value. Recently, specialized market places for patent transactions have emerged that allow us for the first time to directly observe patent's private value. One of the most prominent market places for patents is Ocean Tomo, a platform that offers periodical patent auctions. We make use of this auction data to empirically test predictions on patent value identifiers on real-world auction prices. We find empirical support for forward citations and the patent's family size; however, both indicators explain only a small variance in patent value. In contrast, our full model explains a large share of variance, making us optimistic that with increased directly observed patent value, such models can be useful tools in patent valuation.  相似文献   

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