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831.
We estimate a two-step control-function model that relates incumbent prices for small-business telecommunications services to the number of facilities-based entrants, cost, demand, regulatory conditions, and a correction for endogenous market structure. Results show that the price effects from entry are understated in ordinary least squares regressions. When controlling for endogeneity, prices are negatively related to the number of entrants, indicating that markets without a competitive presence could exhibit market power. These findings should prove helpful to the Federal Communications Commission and other State regulators determining the conditions under which price and other forms of regulation may be relaxed.  相似文献   
832.
Integrating ecosystem services into conservation assessments: A review   总被引:8,自引:0,他引:8  
A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.  相似文献   
833.
834.
The purpose of this paper is to explain differences in the productivity of investment across 84 rich and poor countries over the period 1980–2011, and to test the orthodox neoclassical assumption of diminishing returns to capital. The productivity of investment is measured as the ratio of the long-run growth of GDP to a country’s gross investment ratio. Twenty potential determinants are considered using a general-to-specific model selection algorithm. Education, government consumption, geography, export growth, openness, political rights and macroeconomic instability are the most important variables. The data also suggest constant returns to capital, so investment and the determinants of productivity of investment differences matter for long-run growth.  相似文献   
835.
This paper studies the relation between inflation and economic development. The literature is largely silent regarding both the theoretical and empirical perspectives that undeveloped countries endure higher average inflation than developed economies. We present a simple theoretical model linking the inflation phenomenon to the tradition of development economics. Empirical evidence is garnered to test the hypothesis that economic development engenders a downward bias to inflation rates. Through the feasible-GLS estimator in a panel of 65 countries from 2001 to 2011, we aim at listing a number of variables most commonly used to explain differences in the stage of economic development across countries and identifying the most statistically relevant ones to account for differences in inflationary patterns. While our results show that inflation is inversely correlated with the level of the technological content of the economy (measured by share of high-tech exports), human capital and cyclical unemployment, it is directly related to the degree of inflation persistence and terms of trade growth. However, our findings still present an inverse and low correlation between inflation persistence and economic development, implying that development-sensitive variables allowed into the model can only partially account for the differences in inflation at different levels of economic development.  相似文献   
836.
This paper considers the Web as a big data container that can be used by Technology Observatories and administrations to track emerging issues and more specifically emerging technologies. It considers information that is available on the Internet for free from different sources, and proposes a framework that can be useful to characterise them and to detect patterns of dissemination. This framework is made up of 30 metrics obtained from different kinds of sources (general web, patents, scholars?…). Some of them are obtained directly as the number of hits retrieved by queries on a search engine, and other ones calculated by means of ratios. This paper contains the development of a complete case that utilises this framework to characterise emerging technologies included in the well-known Hype Cycle for Emerging Technologies, in this case the 2015 release1 and to analyze patterns of dissemination of these technologies on the Internet.  相似文献   
837.
Adoption of a new ICT tool in the fisheries sector depends on several factors such as ease of use, affordable cost, information, and time. All these factors determine the preference of an existing tool over others for productivity enhancement. Which ICT tool is more beneficial than others is a continuing debate among researchers. However, the literature currently lacks detailed studies of fishermen criteria for selecting the best ICT tools in the marine fisheries sector. This paper is based on a framework which explains the factors influencing the adoption of ICT tools for the better fish catch, with the help of a multi-criteria decision making approach, called Analytic Hierarchy Process. Also, in the study we have compared the results of analysis using AHP with popular method TOPSIS and the obtained results were validated. The Study also assesses scientifically, which is the most important ICT tool for fishing through a case study in Northern and Southern parts of Kerala, a state in the southern India. The Study finds that Global Positioning System (GPS) is the most beneficial and important ICT tool in marine fishing. In contrast to the earlier studies, the results show that wireless set is important than other tools like mobile phone and echo-sounder for multi-day fishing. The cost-benefit analysis also supports findings of the study.  相似文献   
838.
In combinatorial models of innovations, new technologies are built from combinations of pre-existing technological components. Researchers learn which components work well together by observing previously successful combinations and the pool of ideas can be ‘fished out’, i.e. exhausted, if it is not ‘restocked’ by the discovery of novel connections. We first show US patents have made increasingly less novel connections among technological constituents since the 1950s, and that the number of technological fields to which these connections are applicable has stopped growing since the 1980s. We then estimate the parameters of an ideas production function, and find parameter estimates consistent with technology fields being fished out if not continually restocked by the discovery of novel connections between technological components. We use the ideas production function to estimate the number of new patent applications induced by each patent granted between 1926 and 2001, and show this number has trended downward since the 1940s.  相似文献   
839.
The paper examines the productivity levels of the largest banks operating in the Eastern European countries over the period of the ongoing European financial crisis. Specifically, the analysis covers the periods of U.S. subprime crisis, the global financial crisis and the sovereign debt crisis. By adopting a fully nonparametric framework, it provides a probabilistic version of a directional input-oriented Malmquist productivity index alongside with its main decomposition. The results from the analysis suggest that banks have faced a deterioration of their productivity levels between the examined periods. It is evident that during the initiation of European sovereign debt crisis, the banks have weakened their ability to utilize efficiently their inputs of production and their ability to realize scale economies.  相似文献   
840.
This paper addresses the problem of redesigning a supply chain network with multiple echelons and commodities. The problem belongs to a comprehensive class of network redesign problems previously introduced in the literature. Redesign decisions comprise the relocation of existing facilities to new sites under an available budget over a finite time horizon, the supply of commodities by upstream facilities, the inventory levels at storage facilities, and the flow of commodities through the network. The problem is modeled as a large-scale mixed-integer linear program. Feasible solutions are obtained by using a tabu search procedure that explores the space of the facility location variables. The latter prescribe the time periods in which changes in the network configuration occur. They are triggered by the setup of new facilities, which operate with capacity transferred from the existing facilities, and by closing the latter upon their entire relocation. As the problem is highly constrained, infeasible solutions with excess budget are allowed during the course of the search process. However, such solutions are penalized for their infeasibility. Computational experiments on realistically sized randomly generated instances indicate that this strategic oscillation scheme used in conjunction with tabu search performs very well.  相似文献   
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