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The computer revolution took very long to pay off in productivity growth in the computer-using sectors. The relative wage of skilled workers, however, has risen sharply from the early days of the computer revolution onward. As skilled workers wages reflect their productivity, the two observations together pose a puzzle.This paper provides a micro-based explanation for the long diffusion period of the computer revolution. The general equilibrium model of growth zooms in on the research process and provides an explanation for sluggish growth with booming relative wages of the skilled. Technological progress in firms is driven by research aimed at improving the production technology (innovation) and by assimilation of ideas or principles present outside the firm (learning). A new General Purpose Technology (GPT) like the computer revolution generates an initial slowdown in economic growth and an increase in the skill premium.Acknowledgement I am indebted to Theo van de Klundert for suggestions and encouragement. Suggestions by Jan Boone, Bas Jacobs, Patrick Francois, Henri de Groot, Lex Meijdam, Niek Nahuis Sjak Smulders, Harald Uhlig and anonymous referees have contributed to the paper.  相似文献   
124.
Beatty, Petacchi, and Zhang investigate the role of two hedge commitment mechanisms??interest rate protection covenants and accounting conservatism??in reducing agency costs of debt. Using a large sample of syndicated loan agreements, they provide evidence that borrowers required to hedge interest rate risk through interest rate protection covenants receive lower interest rate charges. However, borrowers who voluntarily hedge interest rate risks receive lower rates only if they implement conservative financial reporting. The authors conclude that the benefits of hedging are realized only when borrowers can credibly commit to maintain hedge positions once a syndicated loan is issued. While the evidence provided by the authors is novel and interesting, I argue that the empirical assessment of hedge benefits is more complex. In addition, there are still some important open issues left unanswered that could be tackled by future research.  相似文献   
125.
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   
126.
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   
127.
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   
128.
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   
129.
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   
130.
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   
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