{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T07:14:42Z","timestamp":1772608482651,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,11,28]],"date-time":"2018-11-28T00:00:00Z","timestamp":1543363200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["2016\/16897-7"],"award-info":[{"award-number":["2016\/16897-7"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001807","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de S\u00e3o Paulo","doi-asserted-by":"publisher","award":["2016\/25682-5; 2013\/07375-0"],"award-info":[{"award-number":["2016\/25682-5; 2013\/07375-0"]}],"id":[{"id":"10.13039\/501100001807","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["305940\/2010-4"],"award-info":[{"award-number":["305940\/2010-4"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Ministerio de Econom\u00eda y Competitividad","doi-asserted-by":"publisher","award":["FIS2017-87519-P"],"award-info":[{"award-number":["FIS2017-87519-P"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010664","name":"H2020 Future and Emerging Technologies","doi-asserted-by":"publisher","award":["Dolfins 640772"],"award-info":[{"award-number":["Dolfins 640772"]}],"id":[{"id":"10.13039\/100010664","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010067","name":"Government of Aragon","doi-asserted-by":"publisher","award":["E36-17R"],"award-info":[{"award-number":["E36-17R"]}],"id":[{"id":"10.13039\/501100010067","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The worldwide trade network has been widely studied through different data sets and network representations with a view to better understanding interactions among countries and products. Here we investigate international trade through the lenses of the single-layer, multiplex, and multi-layer networks. We discuss differences among the three network frameworks in terms of their relative advantages in capturing salient topological features of trade. We draw on the World Input-Output Database to build the three networks. We then uncover sources of heterogeneity in the way strength is allocated among countries and transactions by computing the strength distribution and entropy in each network. Additionally, we trace how entropy evolved, and show how the observed peaks can be associated with the onset of the global economic downturn. Findings suggest how more complex representations of trade, such as the multi-layer network, enable us to disambiguate the distinct roles of intra- and cross-industry transactions in driving the evolution of entropy at a more aggregate level. We discuss our results and the implications of our comparative analysis of networks for research on international trade and other empirical domains across the natural and social sciences.<\/jats:p>","DOI":"10.3390\/e20120909","type":"journal-article","created":{"date-parts":[[2018,11,28]],"date-time":"2018-11-28T11:43:44Z","timestamp":1543405424000},"page":"909","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Unfolding the Complexity of the Global Value Chain: Strength and Entropy in the Single-Layer, Multiplex, and Multi-Layer International Trade Networks"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6204-5552","authenticated-orcid":false,"given":"Luiz","family":"A. Alves","sequence":"first","affiliation":[{"name":"Institute of Mathematics and Computer Science, University of S\u00e3o Paulo, S\u00e3o Carlos, SP 13566-590, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6910-0112","authenticated-orcid":false,"given":"Giuseppe","family":"Mangioni","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria Elettrica, Elettronica e Informatica, University of Catania, 95125 Catania, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francisco","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Institute of Mathematics and Computer Science, University of S\u00e3o Paulo, S\u00e3o Carlos, SP 13566-590, Brazil"},{"name":"Mathematics Institute, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK"},{"name":"Centre for Complexity Science, University of Warwick, Coventry CV4 7AL, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7596-4806","authenticated-orcid":false,"given":"Pietro","family":"Panzarasa","sequence":"additional","affiliation":[{"name":"School of Business and Management, Queen Mary University of London, London E1 4NS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0895-1893","authenticated-orcid":false,"given":"Yamir","family":"Moreno","sequence":"additional","affiliation":[{"name":"Department of Theoretical Physics, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"Institute for Biocomputation and Physics of Complex Systems, University of Zaragoza, 50009 Zaragoza, Spain"},{"name":"The Institute for Scientific Interchange Foundation, 10126 Torino, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14103","DOI":"10.1038\/ncomms14103","article-title":"The geometric nature of weights in real complex networks","volume":"8","author":"Allard","year":"2017","journal-title":"Nat. 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