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11.
Abstract

This paper analyzes the use and effectiveness of patents and trade secrets designed to protect innovation. While previous studies have usually considered patents and trade secrets as substitutes for one another, we investigate to what extent and in what situations the two protection methods are used jointly. We identify protection strategies for single innovation firms and hence overcome the assignment problem of existing empirical studies, that is, whether firms using both protection methods do so for the same innovation or for different innovations. Employing firm panel data from Germany, we find fairly few differences between the determinants for choosing secrecy and patenting. Single innovators that combine both strategies, 39% of the group, tend to aim at a higher level of innovation and act in a more uncertain technological environment. Firms combining both protection methods yield significantly higher sales with new-to-market innovations, providing some evidence for a complementarity of the two protection methods.  相似文献   
12.
We investigate the impact of product market competition on returns to skills in Italy using a longitudinal dataset on individual working histories. This impact is identified using three exogenous shocks affecting competition: the unforeseen devaluation of the Lira in 1992, its return to a fixed exchange regime in 1996 and the market liberalisation in the utility and transport sectors in the late 1990s–early 2000s. We analyse how firm heterogeneity and shocks of different types and signs affect the impact of competition on skill premia. We find that opposite shocks have opposite effects: an increase (resp. decrease) in international competition increases (resp. decreases) skill premia. Moreover, international shocks have greater effects on medium sized firms, while domestic liberalisation shocks have greater effects on large incumbents.  相似文献   
13.
We investigate how perceived parents’ performance in entrepreneurship (PPE) affects the entrepreneurial career intentions of offspring. We argue that while perceived PPE enhances offspring’s perceived entrepreneurial desirability and feasibility because of exposure mechanisms, it inhibits the translation of both desirability and feasibility perceptions into entrepreneurial career intentions due to upward social comparison mechanisms. Thus, perceived PPE acts as a double-edged sword for the intergenerational transmission of entrepreneurship. Our predictions are tested and confirmed on a sample of 21,895 individuals from 33 countries. This study advances the literature on intergenerational transmission of entrepreneurship by providing a foundation for understanding the social psychological conditions necessary for such transmission to occur.  相似文献   
14.
In this contribution, we present a virtual voyage through 3D structures generated by chaotic mixing of magmas and numerical simulations with the aim to highlight the power of 3D representations in the understanding of this geological phenomenon. In particular, samples of mixed juveniles from Salina island (Southern Italy) are reconstructed in 3D by serial lapping and digital montage and numerical simulations are performed by using a 3D chaotic dynamical system. Natural and simulated magma mixing structures are visualized by using several multimedia tools including animations and “virtual reality” models. It is shown that magma interaction processes can generate large spatial and temporal compositional heterogeneities in magmatic systems. The same topological structures are observed in both 3D reconstructed rock samples and chaotic numerical simulations, indicating that the mixing of magmas is governed by chaotic dynamics. The use of 3D multimedia models gives the opportunity to penetrate into magma mixing structures and to understand their significance in the context of magma dynamics. Such an approach is very powerful since multimedia tools can strongly capture the attention of the reader bringing him/her into an interactive and memorable geological experience.  相似文献   
15.
We develop methods to solve general equilibrium models in which forward‐looking agents are subject to waves of pessimism, optimism, and uncertainty that turn out to critically affect macroeconomic outcomes. Agents in the model are fully rational and conduct Bayesian learning, and they know that they do not know. Therefore, agents take into account that their beliefs will evolve according to what they will observe. This framework accommodates both gradual and abrupt changes in beliefs and allows for an analytical characterization of uncertainty. We use a prototypical Real Business Cycle model to illustrate the methods.  相似文献   
16.
Small Business Economics - There is wide consensus about the importance of green technologies in achieving superior economic and environmental performances. However, the literature on their...  相似文献   
17.
The ability to estimate the intensity of accidental dust explosions is an essential prerequisite of methodologies intended to provide design guidelines for the protection of equipment and buildings where combustible dusts are being handled. In general, the severity of an explosion depends on the type of dust involved, its physical properties (such as particle size and moisture content), the characteristics of the interested volume (size, shape, presence of vents, and blockages), the strength and type of the ignition source, and the conditions of the environment (air flow, turbulence).  相似文献   
18.
The European Commission put forward its strategy for the 2010–2020 period in its Europe 2020 Communication. Inequality should be seen as a cornerstone of both sustainable and inclusive growth. In fact, unequal societies are also more unstable societies (i.e. unsustainable) and more polarised (i.e. exclusive). The analysis of available data and the established consensus in the literature shows four main stylised facts.  相似文献   
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