{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T19:55:29Z","timestamp":1767902129800,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T00:00:00Z","timestamp":1639440000000},"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 is an informal and sketchy review of five topical, somewhat unrelated subjects in quantitative finance and econophysics: (i) models of price changes; (ii) linear correlations and random matrix theory; (iii) non-linear dependence copulas; (iv) high-frequency trading and market stability; and finally\u2014but perhaps most importantly\u2014(v) \u201cradical complexity\u201d that prompts a scenario-based approach to macroeconomics heavily relying on Agent-Based Models. Some open questions and future research directions are outlined.<\/jats:p>","DOI":"10.3390\/e23121676","type":"journal-article","created":{"date-parts":[[2021,12,14]],"date-time":"2021-12-14T09:34:25Z","timestamp":1639474465000},"page":"1676","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Radical Complexity"],"prefix":"10.3390","volume":"23","author":[{"given":"Jean-Philippe","family":"Bouchaud","sequence":"first","affiliation":[{"name":"Capital Fund Management, 75007 Paris, France"},{"name":"Acad\u00e9mie des Sciences, 75006 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,14]]},"reference":[{"key":"ref_1","unstructured":"Bachelier, L. (2021, December 13). Theory of Speculation. 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