노트 : 24th European Regional Conference of the International Telecommunication Societ
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TEMEP Discussion Papers is intended to serve as an outlet for publishing research about theoretical, methodological and applied aspects of industrial economics, especially those related to the institute’s areas of specialization, namely... more
TEMEP Discussion Papers is intended to serve as an outlet for publishing research about theoretical, methodological and applied aspects of industrial economics, especially those related to the institute’s areas of specialization, namely management of technology, information and telecommunication, health and energy industries, as well as development economics infrastructure. In particular submission of studies analyzing current technology and industry related issues and discussion of their implications and possible alternative policies are welcome. The objective is to gain insights into important policy issues and acquiring a balanced viewpoint of policymaking, technology management and economics which enable us to identify the problems in the industries accurately and to come up with optimal and effective guidelines. Another important aim with the series is to facilitate communication with external research institutes, individual researchers and policy makers. Research disseminated ...
Through the advancement of information technology, a new type of innovation could emerge. This innovation type suggests a leading company to open up its software service platform to customers as well as competitors. Many innovation... more
Through the advancement of information technology, a new type of innovation could emerge. This innovation type suggests a leading company to open up its software service platform to customers as well as competitors. Many innovation studies have been performed in the past, in order to understand the structure of this interaction among platform users from a network science perspective. By focusing on the internal mechanisms of software vendors only, these studies missed the role of platform providers in the innovation process though. In this paper, we fill this gap by investigating the impact of platform providers on the structure of a software service network. The empirical data about the software services network has been gathered from Salesforce.com AppExchange. It is used to identify the clusters in the network and the network position of each software service. Using the Kruskal-Wallis test, we infer from those results that the network position of the platform providers software services is different from the network position of software services of third party vendors. In particular, our results show that the software services released by the platform provider locate at hub positions, while those released by third party vendors locate at positions interconnecting clusters. These results imply a role division between platform providers and third party vendors in this innovation type. The former leads the overall innovation on the platform, while the third party vendors interconnect software services of different categories.
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While technology convergence strategy is highly emphasized for firms in various industries, its effect on firms market performance is significantly underexplored. This study examines the effect of ...
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In recent studies, Information and Communication Technologies have been key drivers of innovation and economic growth throughout the world. Because the Information and Communication Technology products and services require intensive... more
In recent studies, Information and Communication Technologies have been key drivers of innovation and economic growth throughout the world. Because the Information and Communication Technology products and services require intensive knowledge, leading countries invested in their innovation systems to operate more effectively and efficiently. Studies on innovation have investigated the knowledge base of countries and their respective relationships with their national institutions, and subsequent economic growth to identify factors which have led to success. However, the approaches of previous studies omit the constituents of the knowledge base while focusing on quantitative aspects such as size. In this article, I propose a novel approach to exploring the knowledge base at a global level by undertaking a network analysis of patents. In this framework, the global knowledge network is defined as a set of countries and respective technological similarities between countries as vertices ...
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ABSTRACT Service providers that own Web2.0 services allow Internet users not only to access their Web2.0 services but also to create new Web2.0 services (mashups) based on theirs. This creation of mashups generates the Web2.0 service... more
ABSTRACT Service providers that own Web2.0 services allow Internet users not only to access their Web2.0 services but also to create new Web2.0 services (mashups) based on theirs. This creation of mashups generates the Web2.0 service network, in which a node represents a Web2.0 service and a link between two nodes represents a mashup using the two Web2.0 services linked. Since this Web2.0 service network is constructed without the control of a single entity (i.e., it is self-organizing), the network topology of the Web2.0 service network shows the scale-free characteristic. With respect of the weighting of those links, however, there are different approaches. Prior research either considered binary links or links that are weighted by summing up the number of mashups. Since the last approach might overestimate the strength of the link, we calculate the link weights according to Newman’s approach in this paper. Based on this weighted graph of the Web2.0 service network, we investigate the topology of the weighted graph and examine the pattern of Web2.0 service creations. Our results show that the Newman-based weighted graph of the Web2.0 service network shows the characteristics of a scale-free network and a small-world network.
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ABSTRACT One of the important characteristics of Web2.0 is the collaboration between Web2.0 service providers. They allow users (i.e., providers, developers, consumers) to combine their services. The prerequisite for this collaboration is... more
ABSTRACT One of the important characteristics of Web2.0 is the collaboration between Web2.0 service providers. They allow users (i.e., providers, developers, consumers) to combine their services. The prerequisite for this collaboration is openness of the Web2.0 service system. Although the Web2.0 technology allows the linking of different heterogeneous Web2.0 services freely, it is only assumed that the Web2.0 system is socially open as well. Until now, it has not been studied whether it is socially open and, if so, to what degree. In this paper, we address this shortcoming by creating and analyzing the Web2.0 service network. The nodes of this network are Web2.0 services and links represent the existence of mashups. In order to measure how much the Web2.0 service network is socially open, we use six openness indices, which are based on Krackhardt and Stern¡¯s EI-Index. Our results show that the Web2.0 is not fully socially open. The reason is that users of Web2.0 services do not leverage the openness provided by the technology. Instead, they prefer using Web2.0 services of those providers that they already know, i.e. the ownership of the service impacts the users¡¯ choices.
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One of the most important properties of self- organized networks is their scale-free property. Prior research proved empirically and theoretically that scale-free networks emerge under the preferential attachment rule. However, a few... more
One of the most important properties of self- organized networks is their scale-free property. Prior research proved empirically and theoretically that scale-free networks emerge under the preferential attachment rule. However, a few empirical studies also show that empirical networks diverge from the structure of scale-free networks. Empirical networks exhibit a lower exponent of the power law distribution than constructed scale-free
Research Interests: Computer Science, Collaborative Networks, Network Formation, Network Design, Network evolution, and 13 moreScale-Free Networks, Complex network, Mobile Peer-to-Peer Network, Hyperlink, Empirical Study, Scale free network, Self Organization, Economic Model, Assortativity, Social Network Analysis, Network Model, Power Law Distribution, and evolutionary model
One of the notable trends in the software industry is that software vendors provide their software on a platform as a service. Software users consume those software services or compose new services by combining those existing software... more
One of the notable trends in the software industry is that software vendors provide their software on a platform as a service. Software users consume those software services or compose new services by combining those existing software services. The software vendors, their services, software users, and the platform represent an open innovation system. Collective intelligence is the underlying mechanism for the cooperation between the users of the system, i.e. their continuous reuse of existing software services for the creation of new services. A successfully working software services system (i.e. collective intelligence system) is a system that is continuously adapted by its users to meet their needs. The evolution of this software-as-a-service (SaaS) innovation system and the behavior of SaaS users within this system are still unknown. In this paper, we describe the evolution of a SaaS network. The SaaS network consists of nodes (i.e. software services with open interfaces) and lin...
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Service networks can be considered to be open innovation systems. It has led to research on the structure of these networks, concentrating on the static network topology and its effect on innovation. However, the research misses the... more
Service networks can be considered to be open innovation systems. It has led to research on the structure of these networks, concentrating on the static network topology and its effect on innovation. However, the research misses the changes of network positions over time. In this paper, we examine the changes of nodes’ positions in a software service network. The software service network has been built from empirical data. In this network, a node represents a Software-as-a-Service (SaaS) service and a link denotes a re-use of existing software services through a new service. Our results suggest that: first, software services undergo life cycles in their network positions; second, some software services achieve to hub position in their life cycle while others a core position; and third, an innovation trend appears at service category level not just by a single service. These results imply that innovation studies should not only consider static network positions and topologies but also trends of changing positions within the network.
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Cloud computing, which can be described as a technology for provisioning computing infrastructure as a service, runtime platform as a service, and software as a service, is considered as a keystone for innovation in the IT area. However,... more
Cloud computing, which can be described as a technology for provisioning computing infrastructure as a service, runtime platform as a service, and software as a service, is considered as a keystone for innovation in the IT area. However, a limiting factor to innovation through cloud computing could be the economies of scale and network externalities that give more benefits to larger cloud providers. Due to the economies of scale and network externalities in an oligopolistic environment, a giant cloud provider can offer resources at lower cost than smaller providers. To overcome the disadvantage of small clouds, some research proposes architectures, in which small clouds can federate through common virtual interfaces. Therefore, academy and industry ask whether the federation of small cloud providers is economically feasible and can compete with a giant cloud provider. However, it is hard to solve those problems because the specifications of a cloud federation and the conditions of cloud market are unclear. To fill this gap, in this paper, we survey the conceptual background of cloud computing and the federation of small cloud providers. The results of this paper are expected to guide how to define the economic problems on cloud federation and provide constraints to the problems.
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Although there is much research on network formation based on the preferential attach- ment rule, the research did not come up with a formula that, on the one hand, can re- produce shapes of cumulative degree distributions of empirical... more
Although there is much research on network formation based on the preferential attach- ment rule, the research did not come up with a formula that, on the one hand, can re- produce shapes of cumulative degree distributions of empirical complex networks and, on the other hand, can represent intuitively theories on individual behavior. In this paper, we propose a formula that closes this gap by integrating into the formula for the preferential attachment rule (i.e., a node with higher degree is more likely to gain a new link) a repre- sentation of the theory of individual behavior with respect to nodes preferring to connect to other nodes with similar attributes (i.e., homophily). Based on this formula, we simulate the shapes of cumulative degree distributions for different levels of homophily and five different seed networks. Our simulation results suggest that homophily and the preferential attachment rule interact for all five types of seed networks. Surprisingly, the resulting cumulative degree distribution in log-log scale always shifts from a concave shape to a convex shape, as the level of homophily gets larger. Therefore, our formula can explain intuitively why some of the empirical complex networks show a linear cumulative degree distribution in log-log scale while others show either a concave or convex shape. Furthermore, another major finding indicates that homophily makes people of a group richer than people outside this group, which is a surprising and significant finding.
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As software vendors provide their software as a service (SaaS) and allow users to access the software functions via open interfaces, the innovation style has shifted from local innovation of a software user, to collective innovation of an... more
As software vendors provide their software as a service (SaaS) and allow users to access the software functions via open interfaces, the innovation style has shifted from local innovation of a software user, to collective innovation of an entire system of users and software. This new innovation trend directs the innovation research to the structural and evolutionary patterns of SaaS networks, in which a node represents a software service and a link the combined use of two software services for provisioning a new service. However, prior research concentrates only on the static properties of network structure and the position of nodes in the network, but misses the dynamics in the evolution context. In this paper, we close this gap by investigating the trend of centralities of five representative software services in a SaaS network. The data has been obtained from www.programmableweb.com. Our results suggest that each software service of a SaaS network follows the typical life cycle from growth to decline. In addition to this, the innovation trend shifts from image services to social networking services, involving a transition of network structure. Our results also show the necessity of innovation studies that investigate the changing patterns of evolving innovation networks.
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PurposeThe purpose of this research is to empirically analyse the structure of the Web 2.0 service network and the mechanism behind its evolution over time.Design/methodology/approachBased on the list of Web 2.0 services and their mashups... more
PurposeThe purpose of this research is to empirically analyse the structure of the Web 2.0 service network and the mechanism behind its evolution over time.Design/methodology/approachBased on the list of Web 2.0 services and their mashups that is provided on Programmableweb, a network of Web 2.0 services was constructed. Within this network a node represents a Web 2.0 service with an open API, and a link between two nodes represents the existence of a mashup service that uses the two nodes.FindingsThe findings suggest that the evolution of the Web 2.0 service network follows the preferential attachment rule although the exponent of the preferential attachment is lower than for other networks following a preferential attachment rule. Additionally the results indicate that the Web 2.0 service network evolves to a scale‐free network but the exponent of the power law distribution is lower than for other networks.Originality/valueThe research applied social network analysis to the Web 2....
Research Interests: Information Systems, Computer Science, Social Networks, Library and Information Studies, Complex network, and 12 moreWorld Wide Web, Design Methodology, Scale free network, Online Information, Web Service, Network structure, Social Network Analysis, Worldwide Web, Internet, Social Network, service Business, and Power Law Distribution
Abstract We examine whether a time lag exists before the network position of a software service affects its performance. Moreover, we analyze different time lags, using empirical data about software services and their usage for creating... more
Abstract We examine whether a time lag exists before the network position of a software service affects its performance. Moreover, we analyze different time lags, using empirical data about software services and their usage for creating composite services. Our results show that software services in central positions (i.e., high betweenness centrality) attract users the most. The highest effect exhibits, if the time lag is 26–32 months. Our findings are relevant, as they can guide developers in marketing their software services and are expected to impact innovation studies regarding the importance of considering time lags and analyzing complementary knowledge.