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71.
This paper investigates two sourcing strategies of firms, outsourcing and importing, and links these to innovation activities. The authors examine this empirically using firm‐level data for 28 emerging market economies and find robust evidence that outsourcing increases the likelihood to spend on R&D and via this channel raises innovation output, whereas importing increases innovation output, but not R&D. The results hold when implementing an instrumental variables approach. It is found that results crucially depend on the institutional environment in the economy, e.g. property rights and intellectual property rights protection. The results suggest that better institutions magnify the gains from importing, but not from outsourcing. EU countries also reap additional positive innovation effects from importing compared with non‐EU countries.  相似文献   
72.
73.
China is perceived to rely on subsidizing firms in targeted industries to improve their performance and stay competitive. We implement an approach that allows for the joint estimation of direct and indirect effects of subsidies on subsidized and non-subsidized firms. We find that firms that receive subsidies experience a boost in productivity. However, our approach highlights the importance of indirect effects, which are generally neglected in the literature. We find that, in general but not always, non-subsidized firms experience reductions in their productivity growth if they operate in a cluster where other firms are subsidized. These negative externalities depend on the share of firms that receive subsidies in the cluster. Aggregating direct and indirect effects into a (weighted) total effect shows that this negative indirect effect tends to dominate. We interpret our results in light of a simple heterogenous firm model, which highlights that subsidization in a competitive environment of firms may potentially harm non-subsidized firms.  相似文献   
74.
Bankruptcy, Counterparty Risk, and Contagion   总被引:2,自引:0,他引:2  
This paper provides a unifying framework for the modeling ofvarious types of credit risks such as contagion effects. Weargue that Markov chains can efficiently be used to tackle theseproblems. However, our approach is not limited to pricing problemswith contagion. On the theoretical side, we derive pricing formulasfor three building blocks that are generalizations of contingentclaims studied in Lando (1998). These claims can be thoughtof as atoms forming the basis for all credit risk payments.Furthermore, we demonstrate that, in general, all contingentclaims exposed to credit risk satisfy a system of partial differentialequations. This is the key result to calculate prices of creditrisk claims explicitly and efficiently.  相似文献   
75.
76.
Aging is defined as loss of homeostasis which affects all metabolic systems, including DNA. Interspecies comparisons and lessons from the human genetic instability syndromes suggest a correlation between DNA-homeostasis and maximum lifespan, whereas average lifespan depends mainly on environmental factors. Current demographic data suggest a maximum lifespan in humans of 110–115. The average life expectancy at birth has reached 80 years in the wealthy nations and may exceed, at least in females, 90 years by the year 2050. Genetic and biological reasons, but also lifestyle factors, account for the greater longevity of women. Attempt to define a ?longevity“ genotype so far have not been met with success, but carriers of the ApoE4-Allele appear to have a disadvantage. Unlike the situation in model organisms, aging and longevity in humans seem to be influenced by numerous genes and environmental interactions. Most people do not die of old age but of age-related diseases which are frequent because of lack of natural selection against genetic defects that cause late-onset diseases. Moreover, genes causing late-onset diseases show evidence of antagonistic pleiotropy, rendering these genes resistant to removal from our genome. Likewise, thermoinstability of DNA and generation of reactive oxygen species during oxidative phosphorylation are two endogenous sources of genomic instability that limit our lifespan and cannot be overcome without fundamentally altering the biological make-up of our species. Genomic instability causes cancer and accelerates the aging process, as evidenced by the human caretaker gene syndromes which typically show progeroid features. From a genetic point of view, cancer and aging may be moderately delayed and / or mitigated by lifestyle and medical / environmental interventions, but given the constraints of our biological make-up, they cannot be eradicated.  相似文献   
77.
The influence of corporate acquisitions on the behaviour of key inventors   总被引:2,自引:0,他引:2  
The behaviour of key inventors after the acquisition of their company is examined. Key inventors are identified on the basis of their patenting output. They account for a large number of their company's high-quality patents. The analysis of 43 acquisitions shows that key inventors leave to a substantial extent their company or they significantly reduce their patenting performance after the acquisition. Factors influencing the behaviour of key inventors after acquisitions are identified. Implications for the effective management of acquisitions as well as suggestions for further research are outlined.  相似文献   
78.
Parasocial interactions and relationships are a frequently used framework for studies on media reception in communication research. In spite of its long tradition, however, the concept is still in need of several clarifications. Therefore, this article explores ways to increase the explanatory value of the concept. We briefly present major problems of the definition and conceptualization of parasocial interactions and relationships, namely the understanding of the key elements interaction, relationship, and persona, and suggest first ideas for their solution. Subsequently, opportunities are outlined to enhance the concept by integrating other theories and concepts on media reception and interpersonal perception, taking them from communication research and psychology. Finally, we discuss methodological problems in general and specific shortcomings of the quasi-standard measure, the Parasocial-Interaction-Scale.  相似文献   
79.
This article describes the results of a scientific discourse which aimed at exploring the reasons for differences in expert health risk assessment of radio frequency electromagnetic fields of mobile telephony.

It starts with describing the structure of the discourse. Then, the reasons for the conflicting risk assessments are discussed. Differences are due to the selection and evaluation of relevant scientific studies by applying different scientific quality standards, to the methods used for generating a research synthesis and an overall risk evaluation. Consensus could be achieved regarding the selection of and the quality requirements for the scientific studies used for risk assessment as well as their significance for risk evaluation. However, dissent remained about the synthesis of scientific evidence into an overall risk evaluation and about the relevance of the precautionary principle for risk evaluation and its implications for the risk assessment framework.

Based on the analysis of these problems, a transparent, consistent and rational procedure for risk assessment is suggested to facilitate a risk characterization which better meets the demands of policy making and the public for an appropriate risk evaluation.  相似文献   
80.
It is often argued that low-skilled workers have an incentive to escape to the unofficial sector if welfare benefits come too close to the net wage in the official sector. Upper limits of welfare benefits often serve as an instrument to ensure a sufficiently high income differnetial between sectors. However, if unofficial-sector income is insecure, and if a change of sectors is costly, an option value of working in the official sector has to be taken into account. This option value reduces the incentive for lowly skilled workers to give up official-sector jobs. Upper limits of welfare benefits might therefore be defined less restrictively.  相似文献   
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