{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T16:28:31Z","timestamp":1774542511477,"version":"3.50.1"},"reference-count":60,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,15]],"date-time":"2025-02-15T00:00:00Z","timestamp":1739577600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, Technological Development and Innovation of the Republic of Serbia","award":["451-03-47\/2023-01\/200005"],"award-info":[{"award-number":["451-03-47\/2023-01\/200005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematics"],"abstract":"<jats:p>This study investigates the complexity, efficiency, and sectoral interdependencies of the S&amp;P Global BMI indices during critical global events, including the COVID-19 pandemic and the Russia\u2013Ukraine war. The analysis is conducted in three dimensions: (1) evaluating market efficiency using permutation entropy and the Fisher information measure, (2) exploring sectoral alignments through clustering techniques (hierarchical and k-means clustering), and (3) assessing the influence of geopolitical risk using Multifractal Detrended Cross-Correlation Analysis (MFDCCA). The results highlight significant variations in informational efficiency across sectors, with Utilities and Consumer Staples exhibiting high efficiency, while Emerging Markets and Financials reflect lower efficiency levels. Temporal analysis reveals widespread efficiency declines during the pandemic, followed by mixed recovery patterns during the Ukraine conflict. Clustering analysis uncovers dynamic shifts in sectoral relationships, emphasizing the resilience of defensive sectors and the unique behavior of Developed BMI throughout crises. MFDCCA further demonstrates the multifractality in cross-correlations with geopolitical risk, with Consumer Staples and Energy showing stable persistence and Information Technology exhibiting sensitive complexity. These findings emphasize the adaptive nature of global markets in response to systemic and geopolitical shocks, offering insights for risk management and investment strategies.<\/jats:p>","DOI":"10.3390\/math13040641","type":"journal-article","created":{"date-parts":[[2025,2,17]],"date-time":"2025-02-17T11:31:17Z","timestamp":1739791877000},"page":"641","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Sectoral Efficiency and Resilience: A Multifaceted Analysis of S&amp;P Global BMI Indices Under Global Crises"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6548-5892","authenticated-orcid":false,"given":"Milena","family":"Koji\u0107","sequence":"first","affiliation":[{"name":"Institute of Economic Sciences, Zmaj Jovina 12, 11000 Belgrade, Serbia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6807-4485","authenticated-orcid":false,"given":"Slobodan","family":"Raki\u0107","sequence":"additional","affiliation":[{"name":"Global Association of Risk Professionals, 111 Town Square Place, Jersey City, NJ 07310, USA"}]},{"given":"Jos\u00e9 Wesley Lima da","family":"Silva","sequence":"additional","affiliation":[{"name":"Department of Statistics and Informatics, Federal Rural University of Pernambuco, Recife 52171-900, PE, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5417-0513","authenticated-orcid":false,"given":"Fernando Henrique Antunes de","family":"Araujo","sequence":"additional","affiliation":[{"name":"Federal Institute of Education Science and Technology of Para\u00edba, Campus Patos PB, Acesso Rodovia PB 110, S\/N, Alto da Tubiba, Patos 58700-030, PB, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1007\/s40822-023-00234-y","article-title":"Economic policy uncertainty, geopolitical risk, market sentiment, and regional stocks: Asymmetric analyses of the EU sectors","volume":"13","author":"Bossman","year":"2023","journal-title":"Eurasian Econ. 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