{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,19]],"date-time":"2025-10-19T15:56:42Z","timestamp":1760889402913,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2017,5,24]],"date-time":"2017-05-24T00:00:00Z","timestamp":1495584000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>This paper is an exercise of quantitative dynamic analysis applied to bilateral relationships among partners within two monetary union case studies: the Portuguese escudo zone monetary union (EZMU) and the European euro zone monetary union (EMU). Real world data are tackled and measures that are usual in complex system analysis, such as entropy, mutual information, Canberra distance, and Jensen\u2013Shannon divergence, are adopted. The emerging relationships are visualized by means of the multidimensional scaling and hierarchical clustering computational techniques. Results bring evidence on long-run stochastic dynamics that lead to asymmetric indebtedness mechanisms among the partners of a monetary union and sustainability difficulties. The consequences of unsustainability and disruption of monetary unions have high importance for the discussion on optimal currency areas from a geopolitical perspective.<\/jats:p>","DOI":"10.3390\/e19060245","type":"journal-article","created":{"date-parts":[[2017,5,24]],"date-time":"2017-05-24T12:13:11Z","timestamp":1495627991000},"page":"245","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Entropy Analysis of Monetary Unions"],"prefix":"10.3390","volume":"19","author":[{"given":"Maria","family":"Mata","sequence":"first","affiliation":[{"name":"Faculdade de Economia, Nova School of Business and Economics, Campus de Campolide, Lisbon 1099-032, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4274-4879","authenticated-orcid":false,"given":"Jose","family":"Machado","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Institute of Engineering, Polytechnic Institute of Porto, Porto 4249-015, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,24]]},"reference":[{"key":"ref_1","unstructured":"Peters, E.E. 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