The World Trade Web: using network analysis and machine learning as tools for public policy decision-making

The World Trade Web (WTW) contains a wealth of information that upon rigorous analysis can aid governments in public policy decision-making. In my attempt to provide this valuable input, this dissertation uses two main methods: weighted network analysis and machine learning. First, the topology of the WTW is explored, described, and analyzed. Secondly, the relationship between countries??? trade network characteristics and their income is modeled. Lastly, deep learning is used to predict trade interactions between countries using quantitative, dyadic binary, and categorical variables. Insightful remarks are obtained: countries with higher PCGDP tend to associate with more neighbors that are themselves weaker, reciprocate fewer of their trade links, and trade more strongly with countries that are themselves stronger, and have a higher export to GDP Ratio. The improved trade forecasting model obtained can result in better GDP forecasts, which can aid with the optimization of tariffs, quotas, and subsidies

Does Alliance Formation between National Labor Unions and National Environmental Organizations Exist?

Does alliance formation between national labor unions and national environmental organizations exist? Seven national labor unions and seven national environmental organizations that are representative of the two movements are selected for examination by this study to address this question. The project gathers and analyzes three types of data: documents on the web sites of the selected organizations, interviews with high ranked officials from many of the organizations examined and the hyperlinks or web links from each organization’s web page. An analysis of the document of the web sites and interviews with high ranking officials identifies three issues that national labor unions and national environmental organizations share: global trade/globalization, corporate accountability and human exposure to toxic chemicals. Next, the study examines the hyperlinks from the web sites to discover if they demonstrate a connection between national labor unions, and national environmental organizations. The study found minimal direct web links between national labor unions and national environmental organizations. From the document analysis of the web sites and the interviews conducted with high ranking officials, Warren’s (1967) typology of coalitional (temporary coalitions) and federative (permanent coalitions) arrangement is used to order the efforts of national labor unions and environmental organizations to work together. The AFL-CIO is included among the assessment of organizations participating in coalitional and federative arrangements. Twenty-one coalitional arrangements and 6 federative arrangements are discovered by this study. The majority of coalitional arrangements and 3 of the 6 federative arrangements are associated with the issue of global trade/globalization. The other coalitional and federative arrangements are associated with the issues of corporate accountability, human exposure to toxic chemicals and energy. The issue of energy as a cooperative issue emerged from the discovered coalitional arrangements. The findings of the study indicate that among national labor unions and national environment organizations, industrial labor unions and environmental lobbying organizations have the greatest success in working together. Overall, the ability of national labor unions and national environmental organizations to work together appears to be limited by their lack of shared issues and their inability to align the frames of the issues they do share. Many indicators suggest that national labor unions and national environmental organizations are moving farther away from working together. Besides the lack of shared issues, the factors of conflicts between the labor and the environmental movements, the difficulty of adopting a social justice frame, the adverse political climate, the relationship of the labor and environmental movements to capital/business, the lack of acknowledging coalitional and federative arrangements, the lack of building federative arrangements, and the general difficulties of trying to work together limit cooperation between national labor unions and national environmental organizations. These findings are discussed using a synthesis of the framing perspective, resource mobilization, and the political process model/political opportunity perspective as suggested by Oliver and Myers (2003). The project concludes with an overview of findings, questions for future research and policy recommendations that could improve the ability of national labor unions and environmental organizations to work together

Global Networks of Trade and Bits

Considerable efforts have been made in recent years to produce detailed topologies of the Internet. Although Internet topology data have been brought to the attention of a wide and somewhat diverse audience of scholars, so far they have been overlooked by economists. In this paper, we suggest that such data could be effectively treated as a proxy to characterize the size of the "digital economy" at country level and outsourcing: thus, we analyse the topological structure of the network of trade in digital services (trade in bits) and compare it with that of the more traditional flow of manufactured goods across countries. To perform meaningful comparisons across networks with different characteristics, we define a stochastic benchmark for the number of connections among each country-pair, based on hypergeometric distribution. Original data are thus filtered by means of different thresholds, so that we only focus on the strongest links, i.e., statistically significant links. We find that trade in bits displays a sparser and less hierarchical network structure, which is more similar to trade in high-skill manufactured goods than total trade. Lastly, distance plays a more prominent role in shaping the network of international trade in physical goods than trade in digital services.Comment: 25 pages, 6 figure

Reach and rich : the new economics of information and the provision of on-line legal services in the UK

The paper considers a number of issues including the use of the Web as an opportunity for smaller firms to break free from the traditional indicators of reputation and expertise such as the size and opulence of offices. It also reflects on the use of client-specific Extranets in addition to publicly available Internet sites. The paper concludes that although the Web provides reach, offering richness and the sense of community required for creating and sustaining relationships with potential clients can be difficult. Some suggestions are made for enhancing 'Richness' in Web sites

Complex Networks and Symmetry II: Reciprocity and Evolution of World Trade

We exploit the symmetry concepts developed in the companion review of this article to introduce a stochastic version of link reversal symmetry, which leads to an improved understanding of the reciprocity of directed networks. We apply our formalism to the international trade network and show that a strong embedding in economic space determines particular symmetries of the network, while the observed evolution of reciprocity is consistent with a symmetry breaking taking place in production space. Our results show that networks can be strongly affected by symmetry-breaking phenomena occurring in embedding spaces, and that stochastic network symmetries can successfully suggest, or rule out, possible underlying mechanisms.Comment: Final accepted versio

Link Prediction via Matrix Completion

Inspired by practical importance of social networks, economic networks, biological networks and so on, studies on large and complex networks have attracted a surge of attentions in the recent years. Link prediction is a fundamental issue to understand the mechanisms by which new links are added to the networks. We introduce the method of robust principal component analysis (robust PCA) into link prediction, and estimate the missing entries of the adjacency matrix. On one hand, our algorithm is based on the sparsity and low rank property of the matrix, on the other hand, it also performs very well when the network is dense. This is because a relatively dense real network is also sparse in comparison to the complete graph. According to extensive experiments on real networks from disparate fields, when the target network is connected and sufficiently dense, whatever it is weighted or unweighted, our method is demonstrated to be very effective and with prediction accuracy being considerably improved comparing with many state-of-the-art algorithms

On the Topological Properties of the World Trade Web: A Weighted Network Analysis

This paper studies the topological properties of the World Trade Web (WTW) and its evolution over time by employing a weighted network analysis. We show that the WTW, viewed as a weighted network, displays statistical features that are very different from those obtained by using a traditional binary-network approach. In particular, we find that: (i) the majority of existing links are associated to weak trade relationships; (ii) the weighted WTW is only weakly disassortative; (iii) countries holding more intense trade relationships are more clustered.Comment: To be submitted to APFA 6 Proceedings. 8 pages, 10 figure

Stock portfolio structure of individual investors infers future trading behavior

Although the understanding of and motivation behind individual trading behavior is an important puzzle in finance, little is known about the connection between an investor's portfolio structure and her trading behavior in practice. In this paper, we investigate the relation between what stocks investors hold, and what stocks they buy, and show that investors with similar portfolio structures to a great extent trade in a similar way. With data from the central register of shareholdings in Sweden, we model the market in a similarity network, by considering investors as nodes, connected with links representing portfolio similarity. From the network, we find groups of investors that not only identify different investment strategies, but also represent groups of individual investors trading in a similar way. These findings suggest that the stock portfolios of investors hold meaningful information, which could be used to earn a better understanding of stock market dynamics.Comment: 9 pages, 4 figures, 1 tabl

Null Models of Economic Networks: The Case of the World Trade Web

In all empirical-network studies, the observed properties of economic networks are informative only if compared with a well-defined null model that can quantitatively predict the behavior of such properties in constrained graphs. However, predictions of the available null-model methods can be derived analytically only under assumptions (e.g., sparseness of the network) that are unrealistic for most economic networks like the World Trade Web (WTW). In this paper we study the evolution of the WTW using a recently-proposed family of null network models. The method allows to analytically obtain the expected value of any network statistic across the ensemble of networks that preserve on average some local properties, and are otherwise fully random. We compare expected and observed properties of the WTW in the period 1950-2000, when either the expected number of trade partners or total country trade is kept fixed and equal to observed quantities. We show that, in the binary WTW, node-degree sequences are sufficient to explain higher-order network properties such as disassortativity and clustering-degree correlation, especially in the last part of the sample. Conversely, in the weighted WTW, the observed sequence of total country imports and exports are not sufficient to predict higher-order patterns of the WTW. We discuss some important implications of these findings for international-trade models.Comment: 39 pages, 46 figures, 2 table