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Dynamic Competition in Pharmaceuticals: Patent Expiry, Generic Penetration, and Industry Structure
Magazzini, Laura; Pammolli, Fabio; Riccaboni, Massimo - Volkswirtschaftliche Fakultät, … - 2004
reference to the consequences of patent expiry in different countries. We focus on the competition at the level of single … December 1998, on sales of pharmaceutical products in four countries (USA, UK, Germany, and France) constitute the basis of our … analysis. All the products containing major molecules whose patent expiration date lies between 1986 and 1996 are included in …
Persistent link: https://www.econbiz.de/10005034975
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Innovation and Corporate Dynamics: A Theoretical Framework
Massimo, Riccaboni; Jakub, Growiec; Fabio, Pammolli - Volkswirtschaftliche Fakultät, … - 2011
We provide a detailed analysis of a generalized proportional growth model (GPGM) of innovation and corporate dynamics …
Persistent link: https://www.econbiz.de/10008919764
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Preferential attachment and growth dynamics in complex systems
Yamasaki, Kazuko; Matia, Kaushik; Buldyrev, Sergey V.; … - Volkswirtschaftliche Fakultät, … - 2004
Complex systems can be characterized by classes of equivalency of their elements defined according to system specific rules. We propose a generalized preferential attachment model to describe the class size distribution. The model postulates preferential growth of the existing classes and the...
Persistent link: https://www.econbiz.de/10005031401
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The Growth of Business Firms: Theoretical Framework and Empirical Evidence
Fu, Dongfeng; Pammolli, Fabio; Buldyrev, Sergey V.; … - Volkswirtschaftliche Fakultät, … - 2005
We introduce a model of proportional growth to explain the distribution of business firm growth rates. The model predicts that it is exponential in the central part and depicts an asymptotic power-law behavior in the tails with an exponent ζ = 3. Because of data limitations, previous studies in...
Persistent link: https://www.econbiz.de/10005031404
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Betweenness Centrality of Fractal and Non-Fractal Scale-Free Model Networks and Tests on Real Networks
Kitsak, Maksim; Havlin, Shlomo; Paul, Gerald; … - Volkswirtschaftliche Fakultät, … - 2007
We study the betweenness centrality of fractal and non-fractal scale-free network models as well as real networks. We show that the correlation between degree and betweenness centrality C of nodes is much weaker in fractal network models compared to non-fractal models. We also show that nodes of...
Persistent link: https://www.econbiz.de/10005031411
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A Generalized Preferential Attachment Model for Business Firms Growth Rates: I. Empirical Evidence
Pammolli, Fabio; Fu, Dongfeng; Buldyrev, Sergey V.; … - Volkswirtschaftliche Fakultät, … - 2006
We introduce a model of proportional growth to explain the distribution P(g) of business firm growth rates. The model predicts that P(g) is Laplace in the central part and depicts an asymptotic power-law behavior in the tails with an exponent ζ = 3. Because of data limitations, previous studies...
Persistent link: https://www.econbiz.de/10005034991
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A Generalized Preferential Attachment Model for Business Firms Growth Rates: II. Mathematical Treatment
Buldyrev, Sergey V.; Pammolli, Fabio; Riccaboni, Massimo; … - Volkswirtschaftliche Fakultät, … - 2006
We present a preferential attachment growth model to obtain the distribution P(K) of number of units K in the classes which may represent business firms or other socio-economic entities. We found that P(K) is described in its central part by a power law with an exponent φ = 2+b/(1−b) which...
Persistent link: https://www.econbiz.de/10005035004
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On Size and Growth of Business Firms
De Fabritiis, Gianni; Riccaboni, Massimo; Pammolli, Fabio - Volkswirtschaftliche Fakultät, … - 2003
We study size and growth distributions of products and business firms in the context of a given industry. Firm size growth is analyzed in terms of two basic mechanisms, i.e. the increase of the number of new elementary business units and their size growth. We find a power-law relationship...
Persistent link: https://www.econbiz.de/10005020505
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Global Competitiveness of Indian Pharmaceutical Industry: Trends and Strategies
Pradhan, Jaya Prakash - Volkswirtschaftliche Fakultät, … - 2006
when compared to global peers on pharmaceutical value-added, productivity, research and development and trade performance … Indian pharmaceutical industry from a mere importer and distributor of drugs and pharmaceuticals to an innovation-driven cost … productivity and R&D intensity. A host of competitive strategies, like greenfield direct investment, overseas acquisitions …
Persistent link: https://www.econbiz.de/10005619335
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Tracing Mobile Inventors – The Causality between Inventor Mobility and Inventor Productivity
Hoisl, Karin - Volkswirtschaftliche Fakultät, … - 2006
This paper analyzes the causality between inventor productivity and inventor mobility. The results show that the level … of education has no influence on inventor productivity. Making use of external sources of knowledge, on the contrary, has … a significant effect on productivity. Finally, firm size has a positive impact on productivity. Firm size also …
Persistent link: https://www.econbiz.de/10005187263