{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,24]],"date-time":"2026-04-24T22:40:51Z","timestamp":1777070451228,"version":"3.51.4"},"reference-count":49,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,5,6]],"date-time":"2023-05-06T00:00:00Z","timestamp":1683331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022YFF0800601"],"award-info":[{"award-number":["2022YFF0800601"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["DQJB22Z01-09"],"award-info":[{"award-number":["DQJB22Z01-09"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2022B1212010002"],"award-info":[{"award-number":["2022B1212010002"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Special project for fundamental scientific research of Institute of Geophysics, China Earthquake Administration (CEA)","award":["2022YFF0800601"],"award-info":[{"award-number":["2022YFF0800601"]}]},{"name":"Special project for fundamental scientific research of Institute of Geophysics, China Earthquake Administration (CEA)","award":["DQJB22Z01-09"],"award-info":[{"award-number":["DQJB22Z01-09"]}]},{"name":"Special project for fundamental scientific research of Institute of Geophysics, China Earthquake Administration (CEA)","award":["2022B1212010002"],"award-info":[{"award-number":["2022B1212010002"]}]},{"name":"Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology","award":["2022YFF0800601"],"award-info":[{"award-number":["2022YFF0800601"]}]},{"name":"Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology","award":["DQJB22Z01-09"],"award-info":[{"award-number":["DQJB22Z01-09"]}]},{"name":"Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology","award":["2022B1212010002"],"award-info":[{"award-number":["2022B1212010002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>One important question in earthquake prediction is whether a moderate or large earthquake will be followed by an even bigger one. Through temporal b-value evolution analysis, the traffic light system can be used to estimate if an earthquake is a foreshock. However, the traffic light system does not take into account the uncertainty of b-values when they constitute a criterion. In this study, we propose an optimization of the traffic light system with the Akaike Information Criterion (AIC) and bootstrap. The traffic light signals are controlled by the significance level of the difference in b-value between the sample and the background rather than an arbitrary constant. We applied the optimized traffic light system to the 2021 Yangbi earthquake sequence, which could be explicitly recognized as foreshock\u2013mainshock\u2013aftershock using the temporal and spatial variations in b-values. In addition, we used a new statistical parameter related to the distance between earthquakes to track earthquake nucleation features. We also confirmed that the optimized traffic light system works on a high-resolution catalog that includes small-magnitude earthquakes. The comprehensive consideration of b-value, significance probability, and seismic clustering might improve the reliability of earthquake risk judgment.<\/jats:p>","DOI":"10.3390\/e25050759","type":"journal-article","created":{"date-parts":[[2023,5,8]],"date-time":"2023-05-08T03:00:28Z","timestamp":1683514828000},"page":"759","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Optimized Traffic Light System with AIC and Application to the 2021 M6.7 Yangbi Earthquake Sequence"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9235-2657","authenticated-orcid":false,"given":"Rui","family":"Wang","sequence":"first","affiliation":[{"name":"Department of Earth and Space Science, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Chang","sequence":"additional","affiliation":[{"name":"Institute of Mining Engineering, BGRIMM Technology Group, Beijing 100160, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9997-8505","authenticated-orcid":false,"given":"Peng","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Earth and Space Science, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2867-1362","authenticated-orcid":false,"given":"Miao","family":"Miao","sequence":"additional","affiliation":[{"name":"Department of Earth and Space Science, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiyi","family":"Zeng","sequence":"additional","affiliation":[{"name":"Department of Earth and Space Science, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haixia","family":"Shi","sequence":"additional","affiliation":[{"name":"China Earthquake Networks Center, Beijing 100045, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Danning","family":"Li","sequence":"additional","affiliation":[{"name":"Earthquake Administration of Yunnan Province, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lifang","family":"Liu","sequence":"additional","affiliation":[{"name":"Earthquake Administration of Yunnan Province, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Youjin","family":"Su","sequence":"additional","affiliation":[{"name":"Earthquake Administration of Yunnan Province, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1785\/BSSA0340040185","article-title":"Frequency of earthquakes in California","volume":"34","author":"Gutenberg","year":"1944","journal-title":"Bull. 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