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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">JDS</journal-id>
<journal-title-group><journal-title>Journal of Data Science</journal-title></journal-title-group>
<issn pub-type="epub">1683-8602</issn><issn pub-type="ppub">1680-743X</issn><issn-l>1680-743X</issn-l>
<publisher>
<publisher-name>School of Statistics, Renmin University of China</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">JDS1065</article-id>
<article-id pub-id-type="doi">10.6339/22-JDS1065</article-id>
<article-categories><subj-group subj-group-type="heading">
<subject>Statistical Data Science</subject></subj-group></article-categories>
<title-group>
<article-title>Modeling Dynamic Transport Network with Matrix Factor Models: an Application to International Trade Flow</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Chen</surname><given-names>Elynn Y.</given-names></name><email xlink:href="mailto:elynn.chen@stern.nyu.edu">elynn.chen@stern.nyu.edu</email><xref ref-type="aff" rid="j_jds1065_aff_001">1</xref><xref ref-type="corresp" rid="cor1">∗</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Chen</surname><given-names>Rong</given-names></name><xref ref-type="aff" rid="j_jds1065_aff_002">2</xref>
</contrib>
<aff id="j_jds1065_aff_001"><label>1</label><institution>New York University</institution>, Stern School of Business, <country>United States</country></aff>
<aff id="j_jds1065_aff_002"><label>2</label><institution>Rutgers University</institution>, Department of Statistics, <country>United States</country></aff>
</contrib-group>
<author-notes>
<corresp id="cor1"><label>∗</label>Corresponding author. Email: <ext-link ext-link-type="uri" xlink:href="mailto:elynn.chen@stern.nyu.edu">elynn.chen@stern.nyu.edu</ext-link>.</corresp>
</author-notes>
<pub-date pub-type="ppub"><year>2023</year></pub-date><pub-date pub-type="epub"><day>5</day><month>12</month><year>2022</year></pub-date><volume>21</volume><issue>3</issue><fpage>490</fpage><lpage>507</lpage><supplementary-material id="S1" content-type="document" xlink:href="jds1065_s001.pdf" mimetype="application" mime-subtype="pdf">
<caption>
<title>Supplementary Material</title>
<p>Supplementary material (<xref ref-type="bibr" rid="j_jds1065_ref_003">Chen and Chen</xref>, <xref ref-type="bibr" rid="j_jds1065_ref_003">2022</xref>) contains exploratory analysis of the international trade data used in the present paper and asymmetric export and import analysis from applying Model (2) to the international trade volume data.</p>
</caption>
</supplementary-material><history><date date-type="received"><day>6</day><month>4</month><year>2022</year></date><date date-type="accepted"><day>11</day><month>9</month><year>2022</year></date></history>
<permissions><copyright-statement>2023 The Author(s). Published by the School of Statistics and the Center for Applied Statistics, Renmin University of China.</copyright-statement><copyright-year>2023</copyright-year>
<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
<license-p>Open access article under the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">CC BY</ext-link> license.</license-p></license></permissions>
<abstract>
<p>International trade research plays an important role to inform trade policy and shed light on wider economic issues. With recent advances in information technology, economic agencies distribute an enormous amount of internationally comparable trading data, providing a gold mine for empirical analysis of international trade. International trading data can be viewed as a <italic>dynamic transport network</italic> because it emphasizes the amount of goods moving across network edges. Most literature on dynamic network analysis concentrates on parametric modeling of the connectivity network that focuses on link formation or deformation rather than the transport moving across the network. We take a different non-parametric perspective from the pervasive node-and-edge-level modeling: the dynamic transport network is modeled as a time series of relational matrices; variants of the matrix factor model of <xref ref-type="bibr" rid="j_jds1065_ref_029">Wang et al.</xref> (<xref ref-type="bibr" rid="j_jds1065_ref_029">2019</xref>) are applied to provide a specific interpretation for the dynamic transport network. Under the model, the observed surface network is assumed to be driven by a latent dynamic transport network with lower dimensions. Our method is able to unveil the latent dynamic structure and achieves the goal of dimension reduction. We applied the proposed method to a dataset of monthly trading volumes among 24 countries (and regions) from 1982 to 2015. Our findings shed light on trading hubs, centrality, trends, and patterns of international trade and show matching change points to trading policies. The dataset also provides a fertile ground for future research on international trade.</p>
</abstract>
<kwd-group>
<label>Keywords</label>
<kwd>latent models</kwd>
<kwd>matrix-variate time series</kwd>
<kwd>trading hubs</kwd>
<kwd>weighted relational data</kwd>
</kwd-group>
<funding-group><award-group><funding-source xlink:href="https://doi.org/10.13039/100000001">NSF</funding-source><award-id>DMS-1803241</award-id></award-group><award-group><funding-source xlink:href="https://doi.org/10.13039/100000001">NSF</funding-source><award-id>DMS-1503409</award-id><award-id>DMS-1737857</award-id><award-id>DMS-1803241</award-id><award-id>IIS-1741390</award-id></award-group><funding-statement>Elynn Y. was supported in part by NSF Grants DMS-1803241. Rong Chen was supported in part by NSF Grants DMS-1503409, DMS-1737857, DMS-1803241 and IIS-1741390. </funding-statement></funding-group>
</article-meta>
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