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121.
Civilisations are imagined, ratherm than real, and nations undergoing identity crises typically represent themselves through multiple civilisational visions. Scholars of geopolitics can hardly understand foreign policy without analysing those visions and social contexts, in which they rise and fall. This article selects for analysis three distinct civilisational ideas of Russia – “West,” “Eurasia” and “Euro-East” – associated with Boris Yeltsin, Yevgeni Primakov and Vladimir Putin, respectively. Russia's foreign policy is best understood as reflecting those civilisational ideas rather than merely material power conditions.  相似文献   
122.
MARKET STRUCTURE, PROGRAM DIVERSITY, AND RADIO AUDIENCE SIZE   总被引:1,自引:0,他引:1  
This paper examines the relationships among radio station listenership, the number of program formats, and the number of stations. These relationships are statistically significant and consistent with theory, but the interrelationships are numerically small. The results imply that proposals by the federal Communications Commission and Congress to relax ownership restrictions must induce substantial changes in station numbers in order to noticeably increase programming diversity. Merely modest changes in these numbers will have only small diversity effects. The paper's results also imply that merely mandating the number of formats in a market may not be in the interests of listeners.  相似文献   
123.
This paper develops a model to analyze the emergence of de facto or market defined compatibility standards in the market for PC spreadsheet software over the period 1982–1988. The model is capable of integrating diverse fragments of empirical evidence and a number of important theoretical building blocks, in particular the analysis of gateways between different versions of the same package, product preannouncements, and diverse consumer tastes towards intrinsic quality and network externalities. The model also explores the implications of different functional forms for the relationship between installed base and the value of network externalities. The paper finds that at least some enhancements to the basic model of standards have to be incorporated to offer a reasonable approximation to developments in the PC spreadsheet software market. The simplest model of de facto standards is not able to describe developments in this market.  相似文献   
124.
Abstract

Objectives: Atrial fibrillation (AF) is the most common arrhythmia and a major marker of ischemic stroke risk. Early detection is crucial and, once diagnosed, anticoagulation therapy can be initiated to reduce stroke risk. The aim of this study was to assess the cost-effectiveness of employing an insertable cardiac monitor (ICM), BIOMONITOR, for the detection of AF compared to standard of care (SoC) ECG and Holter monitoring in patients with cryptogenic stroke, that is, stroke of unknown origin and where paroxysmal, silent AF is suspected.

Materials and methods: A Markov model was developed which consisted of five main health states reflecting the potential lifetime evolution of the AF disease: post cryptogenic stroke (index event), subsequent mild, moderate and severe stroke, and death. Sub-states were included to track a patient’s AF diagnostic status and the use of antiplatelet or anticoagulant therapy. AF detection was assumed to result in a treatment switch from aspirin to anticoagulants, except among those with a history of major bleeding. Detection yield and accuracy, clinical actions and treatment effects were derived from the literature and validated by an expert clinician. All relevant costs from a US Medicare perspective were included.

Results and conclusions: An ICM-based strategy was associated with a reduction of 37 secondary ischemic strokes per 1000 patients monitored compared with SoC. Total per-patient costs with an ICM were higher (US$90,052 vs. US$85,157) although stroke-related costs were reduced. The use of an ICM was associated with a base-case incremental cost-effectiveness ratio of US$18,487 per life year gained compared with SoC and US$25,098 per quality-adjusted life year gained, below established willingness-to-pay thresholds. The conclusions were found to be robust over a range of input values. From a US Medicare perspective the use of a BIOMONITOR ICM represents a cost-effective diagnostic strategy for patients with cryptogenic stroke and suspected AF.  相似文献   
125.
Measuring the immeasurable — A survey of sustainability indices   总被引:1,自引:0,他引:1  
Sustainability indices for countries provide a one-dimensional metric to valuate country-specific information on the three dimensions of sustainable development: economic, environmental, and social conditions. At the policy level, they suggest an unambiguous yardstick against which a country's development can be measured and even a cross-country comparison can be performed. This article reviews the explanatory power of various sustainability indices applied in policy practice. We show that these indices fail to fulfill fundamental scientific requirements making them rather useless if not misleading with respect to policy advice.  相似文献   
126.
This paper uses fractional integration models to describe the long‐run dependence of nominal exchange rates in Central and Eastern European countries (CEECs). The analysis is validated using nonparametric, semiparametric and parametric techniques. From comparing the results across the three approaches, it was clear that mean reversion takes places only for the euro exchange rates in Bulgaria, Estonia, and Slovenia. Other exchange rates based on the euro also display mean reversion with the parametric methods. For the US dollar rates, the unit‐root null hypothesis cannot be rejected in any single country, indicating that shocks affecting the exchange rates against the US dollar are of a permanent nature, while those directed against the euro are less persistent, and tend sometimes to disappear in the long run. Policy implications are derived.  相似文献   
127.
This study examines the incidence of research and development (R&D) activities, type of R&D undertaken and the incidence of R&D co-operation among manufacturing firms located in a key urban area of the North East England, a peripheral region of the UK. We have found that over 62% of manufacturing firms in this urban growth area to be R&D active, suggesting that R&D active firms tend to be concentrated in urban area s in a peripheral region, as it is the case in the leading regions. However, the incidence of R&D co-operation was found to be relatively low among R&D active firms. It is also found that the key determinants of undertaking R&D to be the existence of a core competence/product and exporting activities. These findings might be of interest to policy makers promoting economic growth via firm’s R&D activities.  相似文献   
128.
In this paper, we argue that consideration of firm strategy can help illuminate the choices managers make between debt and equity financing. Within an industry, the form of competition that each firm chooses will determine the strategic value to the firm of maintaining financial slack. Our empirical analysis yields strong support for the proposition that financial slack should be a particularly critical strategic imperative for firms pursuing a competitive strategy premised on innovation. We also demonstrate that firms pursuing such a strategy that fail to recognize the value of financial slack are likely to perform poorly. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
129.
Summary. We construct an OLG model with network effects to examine skill obsolescence when individuals can choose technological vintages. In the absence of transfer payments, some regions of the parameter space have unique stationary equilibria, others have unique cyclical equilibria, and others have multiple stationary equilibria. All equilibria are Pareto efficient. However, rat race equilibria can exist in which all agents currently alive prefer a slower rate of progress than occurs in equilibrium. When contemporaneous transfers are allowed, equilibria are unique everywhere, but a cycle still exists, and a rat race can still arise in equilibrium. Allowing intertemporal transfers (debt) ensures that all equilibria are stationary. In the relevant parameter range, the introduction of debt can eliminate cycles and increase the long-run growth rate. No rat race equilibria exist when debt is allowed.Received: 3 January 2002, Revised: 3 June 2004, JEL Classification Numbers: 041, J24, O33. Correspondence to: Ian P. KingEarly versions of this paper were presented at the West Coast Macro Workshop, the Mid-West Macro Meetings, the Canadian Macroeconomics Study Group Meetings, and the Society for Economic Dynamics Meetings. We would like to thank V. V. Chari, Merwan Engineer, Don Ferguson, John Hillas, John Knowles, Dan Peled, Dan Usher, Linda Welling and Julian Wright for helpful comments. We are especially grateful to an anonymous referee for some very useful and substantive comments.  相似文献   
130.
The aim of this article is to test whether the credit market conditions affect the strength of transmission of real estate wealth effects on household consumption in the US economy. Although many different works have dealt with the analysis of the existence of a real estate wealth effect, most of them as a reaction to the dramatic increase of housing prices in several OECD countries, there are only few papers analysing whether the consumption response depends on the positive or negative sign of the wealth shock and, as far as we know, none of them takes the effects of credit market conditions on that asymmetric response into account. This article tries to fill the existing gap in the literature on this matter. From an econometric perspective, we estimate the asymmetries in the consumption response within the momentum threshold autoregressive model (M-TAR) proposed by Enders and Siklos (2001), but following Stevans (2004), it is applied to a multivariate framework. The main results show that the credit market conditions play a significant role in the transmission of changes in real estate wealth to consumption. In addition, we find that there exists an asymmetric behaviour in the US aggregate consumption spending responses to real estate wealth and credit market shocks, which is only significant when a negative shock takes place.  相似文献   
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