Information geodesics for gamma models of communication clustering

Recently, Akyildiz called for further work on non-Poisson models for communication arrivals in distributed networks such as cellular phone systems. The basic ‘random’ model for stochastic events is the Poisson process; for events on a line this resuits in an exponential disiribuuon of intervals between events. Network designers and managers need too monotor and quantify call clustering in order to optimize resaurce usage; the natural reference state from which to measure departures is that arising from a Poisson, process of calls. Here we consider gamma distributions, which contain exponential distributions as a special case. The surface representing gamma models has a natural Riemannian information metric and we obtain some geodesic sprays for this metric. The exponential distributions form a 1-dimensional subspace of the 2-dimensional space of all gamma distributions, so we have an isometric embedding of the random model as a subspace of the gamma models. This geometry may provide an appropriate structure on which to represent clustering as quantifiable departures from randomness and on which to impose dynamic control algorithms to optimize traffic at receiving nodes in distributed communication networks. In practice, we may expect correlation between call arrival times and call duration, reflecting for example peaks of different users of internet services. This would give rise to a twisted product of two surfaces with the twisting controlled by the correlation. Though bivariate gamma models do exist, such as Kibble's, none has tractabie information geometry nor sufficiently general marginal gammas,but a simulation method of approach is suggested.     

Multilevel embeddedness: The case of the global fisheries governance complex

This paper explores how bilateral and multilateral clustering are embedded in a multilevel system of interdependent networks. We argue that in complex systems in which bilateral and multilateral relations are themselves interrelated, such as global fisheries governance, embeddedness cannot be reduced to unipartite or bipartite clustering but implicates multilevel closure. We elaborate expectations for ties’ multilevel embeddedness based on network theory and substantive considerations and explore them using a multilevel ERGM. We find states’ bilateral ties are embedded in their shared membership in multilateral fisheries agreements, which is itself clustered around foci represented by similar content and treaty secretariats.     

Crossing borders with social media: Online social networks and FDI

Social media is embedded in today's internationalization strategy. Companies extend their reach into foreign countries by posting and tweeting. Firms also enhance their mobile capabilities in foreign markets (e.g., knowledge and reputation) through user-generated content in online social networks. Levering on the capabilities-based theory of the multinational enterprise, this paper builds upon a resource-based, industry/network-based, and institution-based view framework. The study provides a comprehensive conceptual and empirical model to explain the effect of social networks on foreign direct investment. Empirical analysis in a global panel dataset of >4500 multinational enterprises suggests that online social networks' activity stimulates foreign capital expenditure and new affiliates. In addition, the article explores the relevance of customer capabilities along with sectoral and institutional moderating effects.     

Global Innovation Networks – Organizations and People

Innovation is increasingly the outcome of global networks that connect geographically dispersed knowledge centers. The international business (IB) literature has developed a sophisticated understanding of the multinational enterprise (MNE) as an organization generates value by integrating knowledge across national borders. We advance this literature by making three key arguments. First we highlight the three megatrends that shape the strategy of the modern MNE: the disaggregation of the value chain into ever narrower activities, the migration of value to knowledge-intensive intangibles and the rise of huge emerging markets like China and India, whose domestic firms can grow to enormous size before venturing abroad. Second, we trace these three megatrends to falling spatial transaction costs, enabled in the main, by digitalization. Third, we draw on earlier research on the generic forms of global linkages, arguing that the IB literature has limited itself to organizational pipelines, while paying relatively little attention to personal relationships. The latter are particularly important in the genesis of both entrepreneurship and radical innovation, but are particularly sensitive to the anti-globalization policies. An environment where technology continues to reduce spatial transaction costs, while policy raises them, strengthens large MNEs at the expense of innovative international new ventures.     

Explaining the Sexuality Gap in Protest Participation

ABSTRACT

This study investigated the relationship between sexual orientations and the protest actions of adults in the United States. Drawing from General Social Survey data from 1996 to 2004, we found that lesbians, gays, and bisexuals were more than twice as likely to protest as heterosexuals. To account for this sexuality gap, we used Patrick Egan’s (2008) political distinctiveness theories to identify possible underlying causes of these protesting differences. After running several regressions, we found that sexuality and protesting relationships were moderated by issues of educational attainment, marital statuses, metropolitan residencies, political partisanships, governmental grievances, and gender role expectations.     

Partners,Institutions and International Currencies: The International Political Foundations for the Rise of the Renminbi

The use of an international currency is not just a natural market phenomenon; it relies heavily on international political foundations. The historical lessons of the four major international currencies—the pound, dollar, euro and yen—show that a strong partner network and a favorable international institutional environment are the two major political foundations for the formation of a stable international currency. The rise of the renminbi, as a late starter looking to become a major international currency, depends not only on the requisite economic conditions but on governmental diplomacy aimed at attracting more monetary cooperation partners and creating international institutions that support its worldwide use. This strategy reinforces the political foundations for the rise of the renminbi. Building a network of partners supporting the renminbi as an international currency and creating a system of international monetary institutions are the real tests of the issuing country’s political leadership. This political leadership capacity has three dimensions: public trust founded on reputation building; a centripetal force driven by provision of benefits; and coercive force applied through sanctions. Comparatively speaking, the renminbi is still in the early stage of its ascent, so the development of its political infrastructure should concentrate mainly on gaining public trust through reputation-building and employing centripetal force involving provision of benefits.     

Bootstrap order selection for SETAR models

In this paper, we investigate the selecting performances of a bootstrapped version of the Akaike information criterion for nonlinear self-exciting threshold autoregressive-type data generating processes. Empirical results will be obtained via Monte Carlo simulations. The quality of our method is assessed by comparison with its non-bootstrap counterpart and through a novel procedure based on artificial neural networks.     

Bayesian Network Structure Learning with Permutation Tests

In literature there are several studies on the performance of Bayesian network structure learning algorithms. The focus of these studies is almost always the heuristics the learning algorithms are based on, i.e., the maximization algorithms (in score-based algorithms) or the techniques for learning the dependencies of each variable (in constraint-based algorithms). In this article, we investigate how the use of permutation tests instead of parametric ones affects the performance of Bayesian network structure learning from discrete data. Shrinkage tests are also covered to provide a broad overview of the techniques developed in current literature.     

Latino Faces,Corporate Ties: Latino Advocacy Organizations and Their Board Membership

Although they have increased exponentially since the 1960s, social scientists know little about ethnic advocacy organizations. These nonprofits are important bridges between underresourced communities and mainstream funding organizations and their directors are established ethnic leaders. Sociologists study interlocking directorates—or shared board membership—to understand how organizations fit together within broader social networks. Network concepts, particularly the theory of institutional isomorphism, suggest that organizations are likely to be similar to the extent they are connected and operate within a common organizational field. We apply this logic to Latino advocacy organizations to examine the underlying source of cohesion across this ethnic field. We ask whether the organizations are tied by interlocking directorates of ethnic elites who sit on their boards of directors or if board members' common affiliation with other elite institutions creates the structural conditions that facilitate potential ideological or behavioral similarity. A social network analysis of five prominent Latino advocacy organizations reveals support for both hypotheses: Latino board members are both embedded in ethnic‐based networks and entrenched within elite organizational webs. This suggests that ethnic elites who sit on the boards of Latino advocacy organizations are also corporate elites, selected for the social capital they bring to these nonprofits.