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841.
Conceptual Knowledge Markup Language: An introduction   总被引:1,自引:0,他引:1  
Kent  Robert E. 《NETNOMICS》2000,2(2):139-169
Conceptual Knowledge Markup Language (CKML) is an application of XML. Earlier versions of CKML followed rather exclusively the philosophy of Conceptual Knowledge Processing (CKP), a principled approach to knowledge representation and data analysis that “advocates methods and instruments of conceptual knowledge processing which support people in their rational thinking, judgment and acting and promote critical discussion”. The new version of CKML continues to follow this approach, but also incorporates various principles, insights and techniques from Information Flow (IF), the logical design of distributed systems. Among other things, this allows diverse communities of discourse to compare their own information structures, as coded in logical theories, with that of other communities that share a common generic ontology. CKML incorporates the CKP ideas of concept lattice and formal context, along with the IF ideas of classification (= formal context), infomorphism, theory, interpretation and local logic. Ontology Markup Language (OML), a subset of CKML that is a self-sufficient markup language in its own right, follows the principles and ideas of Conceptual Graphs (CG). OML is used for structuring the specifications and axiomatics of metadata into ontologies. OML incorporates the CG ideas of concept, conceptual relation, conceptual graph, conceptual context, participants and ontology. The link from OML to CKML is the process of conceptual scaling, which is the interpretive transformation of ontologically structured knowledge to conceptual structured knowledge. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
842.
Daily price adjustments in the U.S. market for natural gas   总被引:1,自引:0,他引:1  
A daily model of cash market for natural gas in the U.S. is presented and estimated over 1997. The model develops the notion that the expected rather than the actual amount of gas in storage (along with weather) and storage changes impact the current daily cash price. These notions are supported by the estimations presented. At the daily observation level, reported changes in storage levels are signals that actual consumption or production are either as expected and result in no price pressure or are not as expected and do result in price pressures.  相似文献   
843.
This paper introduces a new approach to the analysis of endogenous growth effects and uses it to illustrate two novel trade-and-growth links. The approach’s simplicity allows us to introduce scale economies and imperfect competition into the R&D and financial intermediation sectors of a Romer–Grossman–Helpman endogenous growth model. We show that trade liberalisation can stimulate growth via a procompetitive effect in the R&D sector and/or financial sector.  相似文献   
844.
The Johansen approach to estimating long-run cointegration vectorsis used with 1968–91 UK region by industry data to estimatereturns to scale. Thus, this approach has the advantages ofincluding a measure of capital, it overcomes the simultaneityproblems associated with the single-equation Verdoom law, andit involves estimating a correctly specified dynamic model inwhich is embedded the long-run solution(s). The results indicatethat there is substantial evidence that increasing returns arethe norm for the majority of manufacturing industries in Britishregions.  相似文献   
845.
Contingent Valuation: Controversies and Evidence   总被引:47,自引:8,他引:39  
Contingent valuation (CV) has become one of the most widely usednon-market valuation techniques. CV's prominence is due to itsflexibility and ability to estimate total value, includingpassive use value. Its use and the inclusion of passive use valuein benefit-cost analyses and environmental litigation are thesubject of a contentious debate. This paper discusses key areasof the debate over CV and the validity of passive use value. Weconclude that many of the alleged problems with CV can beresolved by careful study design and implementation. We furtherconclude that claims that empirical CV findings are theoreticallyinconsistent are not generally supported by the literature. Thedebate over CV, however, has clarified several key issues relatedto nonmarket valuation and can provide useful guidance both to CVpractitioners and the users of CV results.  相似文献   
846.
Francesca Cornelli, Richard D'Aveni, Andrew Kakabadse, Rosabeth Moss Kanter, Markus Reitzig, Fons Trompenaars and Kim Warren share their latest research.  相似文献   
847.
This paper utilizes the dualistic model of development to analyze the development of three regions: Northeast Asia, China, and India. There are many similarities between the development processes experienced by the first two regions. They involved rapid agricultural growth as a foundation for the growth of labor-intensive manufacturing. However, India's growth process seems to have skipped over the stage of labor-intensive manufacturing growth. Switching to a more labor-intensive growth process is often seen to be dependent on reform of India's labor laws. This paper argues that such reform will not work. The labor intensity of the growth process is dependent on rapid growth in agriculture. Without this, structural change will slow and inequality worsen. The latter will likely result in a deterioration of state effectiveness.  相似文献   
848.
This paper uses a simple model of labor supply extended to allow for home production to understand the extent to which differences in taxes can account for differences in time allocations between the US and Europe. Once home production is included, the elasticity of substitution between consumption and leisure is almost irrelevant in determining the response of market hours to higher taxes. But to account for observed differences in leisure and time spent in home production, one still requires a relatively large elasticity of substitution between consumption and leisure, combined with a relatively small elasticity of substitution between time and goods in home production.  相似文献   
849.
A theory of oligopolistic innovation adoption is developed in which intrafirm diffusions occur because the marginal cost of adoption is increasing in the rate of adoption. The equilibrium intrafirm diffusion curve is S-shaped or concave, as are empirically observed ones. This diffusion curve is more likely to be S-shaped the more competitive the industry, the larger the marginal cost of adoption or the pre-innovation unit cost of production, or the smaller the demand. The diffusion is longer, and so the extent of adoption at any date is lower the more competitive the industry, the larger the marginal cost of adoption or the pre-innovation unit cost of production, or the smaller the demand. A surprising result is that an increase in the unit cost reduction from the innovation has an ambiguous effect on diffusion. Obviously, a larger cost reduction allows each firm to earn a larger flow profit at every date from the same rate of adoption. However, a more subtle effect is that it also allows the firm to earn the same flow of profit with a slower rate of adoption, and so lower adoption costs. That is, the firms also have an incentive to spread out the diffusion over a longer period of time to save on adoption costs.  相似文献   
850.
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