{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T23:13:47Z","timestamp":1769469227286,"version":"3.49.0"},"reference-count":62,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T00:00:00Z","timestamp":1769385600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42271199"],"award-info":[{"award-number":["42271199"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42171201"],"award-info":[{"award-number":["42171201"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002241","name":"Japan Science and Technology Agency (JST) SPRING Program","doi-asserted-by":"publisher","award":["JPMJSP2116"],"award-info":[{"award-number":["JPMJSP2116"]}],"id":[{"id":"10.13039\/501100002241","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJGI"],"abstract":"<jats:p>Activity space represents the spatiotemporal interaction between individuals and their environment. While most studies measure potential activity space using short-term data, few have defined or measured its actual internal structure. This study introduces \u201canchor regions\u201d as the core areas where daily activities are concentrated, and conceptualizes the structure of an individual\u2019s activity space by incorporating the concept of regular locations, anchor regions, potential regular activity space, and potential activity space. Using three months of mobile signaling data from 10,848 residents in Shenzhen, we detected anchor regions via a weighted density-based spatial clustering for applications with noise (DBSCAN) method and categorized individuals into six typical activity space structures based on a rule-based taxonomy. We also figured out the intra- and inter-anchor region mobility pattern of each type. Our results show the following: (1) A total of 80% of activities and 87% of time are concentrated in just 26% of locations, forming anchor regions\u2014with 95% of individuals having no more than five such regions. (2) The total area of anchor regions is merely 0.1% of the potential activity space. (3) Six typical structures of activity space are derived with different combinations of several functional anchor regions, including home, weekday anchors, and daily activity anchors. (4) The spatial patterns of the six types are different, while intra-anchor region mobilities dominate daily movement in all six types. This study provides a region-based, instead of a point-based, perspective interpretation of the anchor points theory, helping to better understand the regularities and internal structure of human activity space. Our conceptual framework and methodology have the potential to help urban and transportation planning practice and policy making.<\/jats:p>","DOI":"10.3390\/ijgi15020056","type":"journal-article","created":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T12:41:16Z","timestamp":1769431276000},"page":"56","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Understanding the Internal Structure of Daily Activity Space from Anchor Regions: Evidence from Long-Time-Series Mobile Signaling Data"],"prefix":"10.3390","volume":"15","author":[{"given":"Xueyao","family":"Luo","sequence":"first","affiliation":[{"name":"College of Urban and Environmental Sciences, Peking University, Beijing 100071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7211-4205","authenticated-orcid":false,"given":"Wenjia","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Architecture and Urban Planning, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanwei","family":"Chai","sequence":"additional","affiliation":[{"name":"College of Urban and Environmental Sciences, Peking University, Beijing 100071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingxue","family":"Xie","sequence":"additional","affiliation":[{"name":"United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan"},{"name":"The Bartlett Centre for Advanced Spatial Analysis, University College London, London W1T 4TJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,26]]},"reference":[{"key":"ref_1","first-page":"22","article-title":"What about people in regional science?","volume":"24","year":"1970","journal-title":"Pap. Reg. Sci."},{"key":"ref_2","unstructured":"Golledge, R.G., and Stimson, R.J. (1997). Spatial cognition, cognitive mapping, and cognitive maps. Spatial Behavior: A Geographic Perspective, The Guilford Press."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.compenvurbsys.2018.04.001","article-title":"Human mobility and socioeconomic status: Analysis of Singapore and Boston","volume":"72","author":"Xu","year":"2018","journal-title":"Comput. Environ. Urban Syst."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1177\/0042098017710122","article-title":"Accessibility planning in American metropolitan areas: Are we there yet?","volume":"56","author":"Proffitt","year":"2019","journal-title":"Urban Stud."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"102938","DOI":"10.1016\/j.jtrangeo.2020.102938","article-title":"Understanding the travel behaviors and activity patterns of the vulnerable population using smart card data: An activity space-based approach","volume":"90","author":"Zhang","year":"2021","journal-title":"J. Transp. Geogr."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1016\/j.tranpol.2003.07.002","article-title":"Activity spaces: Measures of social exclusion?","volume":"10","author":"Axhausen","year":"2003","journal-title":"Transp. Policy"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1007\/s10109-010-0112-x","article-title":"Measuring segregation: An activity space approach","volume":"13","author":"Wong","year":"2011","journal-title":"J. Geogr. Syst."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1481","DOI":"10.1177\/03611981221125210","article-title":"Deconstruction of Commuters\u2019 Activity Space and Social Exclusion under Anchor Point Theory: A Case Study of Kunming, China","volume":"2677","author":"Zheng","year":"2023","journal-title":"Transp. Res. Rec."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1186\/s12942-018-0149-5","article-title":"Capturing exposure in environmental health research: Challenges and opportunities of different activity space models","volume":"17","author":"Laatikainen","year":"2018","journal-title":"Int. J. Health Geogr."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"838","DOI":"10.1016\/j.healthplace.2010.04.009","article-title":"The combined effects of activity space and neighbourhood of residence on participation in preventive health-care activities: The case of cervical screening in the Paris metropolitan area (France)","volume":"16","author":"Cadot","year":"2010","journal-title":"Health Place"},{"key":"ref_11","first-page":"215","article-title":"Consumption and shifting temporalities of daily life in times of disruption: Undoing and reassembling household practices during the COVID-19 pandemic","volume":"18","author":"Greene","year":"2022","journal-title":"Sustain. Sci. Pract. Policy"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1311","DOI":"10.1016\/j.socscimed.2009.07.013","article-title":"From place-based to people-based exposure measures","volume":"69","author":"Kwan","year":"2009","journal-title":"Soc. Sci. Med."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1007\/s11116-016-9719-1","article-title":"Activity space estimation with longitudinal observations of social media data","volume":"43","author":"Lee","year":"2016","journal-title":"Transportation"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1023\/A:1007031809319","article-title":"Two-earner families and their action spaces: A case study of two Dutch communities","volume":"48","author":"Dijst","year":"1999","journal-title":"GeoJournal"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"102499","DOI":"10.1016\/j.apgeog.2021.102499","article-title":"The activity space-based segregation of migrants in suburban Shanghai","volume":"133","author":"Ta","year":"2021","journal-title":"Appl. Geogr."},{"key":"ref_16","first-page":"1","article-title":"Structure and innovation of human activity spaces","volume":"258","author":"Axhausen","year":"2004","journal-title":"Arbeitsberichte Verkehrs-und Raumplanung"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1016\/j.tbs.2018.10.001","article-title":"Exploring centricity of activity spaces: From measurement to the identification of personal and environmental factors","volume":"14","author":"Hasanzadeh","year":"2019","journal-title":"Travel Behav. Soc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1007\/s10708-021-10489-0","article-title":"Use of participatory mapping approaches for activity space studies: A brief overview of pros and cons","volume":"87","author":"Hasanzadeh","year":"2022","journal-title":"GeoJournal"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/04353684.1970.11879340","article-title":"The intra-urban migration process: A perspective","volume":"52","author":"Brown","year":"1970","journal-title":"Geogr. Ann. Ser. B Hum. Geogr."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"36","DOI":"10.2307\/143224","article-title":"Effects of urban spatial structure on individual behavior","volume":"47","author":"Horton","year":"1971","journal-title":"Econ. Geogr."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1016\/S0272-4944(87)80020-8","article-title":"Exploring the anchor-point hypothesis of spatial cognition","volume":"7","author":"Couclelis","year":"1987","journal-title":"J. Environ. Psychol."},{"key":"ref_22","first-page":"341","article-title":"Individual accessibility revisited: Implications for geographical analysis in the twenty-first century","volume":"35","author":"Kwan","year":"2003","journal-title":"Geogr. Anal."},{"key":"ref_23","first-page":"1415","article-title":"How short is long enough? Modeling temporal aspects of human mobility behavior using mobile phone data","volume":"109","author":"Yoo","year":"2019","journal-title":"Ann. Am. Assoc. Geogr."},{"key":"ref_24","first-page":"489","article-title":"Another tale of two cities: Understanding human activity space using actively tracked cellphone location data","volume":"106","author":"Xu","year":"2016","journal-title":"Ann. Am. Assoc. Geogr."},{"key":"ref_25","first-page":"515","article-title":"Effects of data preprocessing methods on addressing location uncertainty in mobile signaling data","volume":"111","author":"Xu","year":"2020","journal-title":"Ann. Am. Assoc. Geogr."},{"key":"ref_26","first-page":"6690295","article-title":"Analysis of Individual\u2019s Activity Space Based on the Cellular Signaling Data","volume":"1","author":"Song","year":"2021","journal-title":"Math. Probl. Eng."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1016\/j.trc.2013.11.003","article-title":"Understanding monthly variability in human activity spaces: A twelve-month study using mobile phone call detail records","volume":"38","author":"Ahas","year":"2014","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/j.tbs.2013.12.002","article-title":"Zooming into individuals to understand the collective: A review of trajectory-based travel behaviour studies","volume":"1","author":"Yue","year":"2014","journal-title":"Travel Behav. Soc."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1179","DOI":"10.1080\/00045608.2015.1081120","article-title":"Modeling and visualizing regular human mobility patterns with uncertainty: An example using Twitter data","volume":"105","author":"Huang","year":"2015","journal-title":"Ann. Assoc. Am. Geogr."},{"key":"ref_30","first-page":"1420","article-title":"Tourism geography through the lens of time use: A computational framework using fine-grained mobile phone data","volume":"111","author":"Xu","year":"2021","journal-title":"Ann. Am. Assoc. Geogr."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"105033","DOI":"10.1016\/j.cities.2024.105033","article-title":"Characterizing the temporally stable structure of community evolution in intra-urban origin-destination networks","volume":"150","author":"Chen","year":"2024","journal-title":"Cities"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"106548","DOI":"10.1016\/j.cities.2025.106548","article-title":"Decomposing urban spatial rhythms: A big-small data fusion framework for activity pattern identification","volume":"169","author":"Liu","year":"2026","journal-title":"Cities"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"103733","DOI":"10.1016\/j.apgeog.2025.103733","article-title":"Exploring neighborhood daily activity patterns from the perspective of mobility using location-based services data: A case study of Shanghai","volume":"183","author":"Wang","year":"2025","journal-title":"Appl. Geogr."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1057\/s41599-023-02577-y","article-title":"Daily rhythm of urban space usage: Insights from the nexus of urban functions and human mobility","volume":"11","author":"Du","year":"2024","journal-title":"Humanit. Soc. Sci. Commun."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"102985","DOI":"10.1016\/j.jtrangeo.2021.102985","article-title":"A multi-view of the daily urban rhythms of human mobility in the Tokyo metropolitan area","volume":"91","author":"Liu","year":"2021","journal-title":"J. Transp. Geogr."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"103366","DOI":"10.1016\/j.apgeog.2024.103366","article-title":"Unveiling the daily rhythm of urban space: Exploring the influence of built environment on spatiotemporal mobility patterns","volume":"170","author":"Varol","year":"2024","journal-title":"Appl. Geogr."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"103665","DOI":"10.1016\/j.tra.2023.103665","article-title":"Need-based approach for modeling multiday activity participation patterns and identifying the impact of activity\/travel conditions","volume":"172","author":"Cho","year":"2023","journal-title":"Transp. Res. Part A Policy Pract."},{"key":"ref_38","unstructured":"Flamm, M., and Kaufmann, V. (2007, January 24\u201328). The concept of Network of Usual Places as a tool for analysing human activity spaces. Proceedings of the 11th World Conference on Transport Research, Berkeley, CA, USA."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1080\/10630731003597306","article-title":"Using mobile positioning data to model locations meaningful to users of mobile phones","volume":"17","author":"Ahas","year":"2010","journal-title":"J. Urban Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1177\/0361198105190200115","article-title":"Analysis of day-to-day variability in an individual\u2019s action space: Exploration of 6-week Mobidrive travel diary data","volume":"1902","author":"Susilo","year":"2005","journal-title":"Transp. Res. Rec."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1016\/j.trc.2014.04.003","article-title":"Urban activity pattern classification using topic models from online geo-location data","volume":"44","author":"Hasan","year":"2014","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"102796","DOI":"10.1016\/j.trc.2020.102796","article-title":"Pattern recognition of daily activity patterns using human mobility motifs and sequence analysis","volume":"120","author":"Su","year":"2020","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"402","DOI":"10.1038\/s41586-020-2909-1","article-title":"The scales of human mobility","volume":"587","author":"Alessandretti","year":"2020","journal-title":"Nature"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"103521","DOI":"10.1016\/j.jtrangeo.2022.103521","article-title":"The 15-minute city for all?\u2013Measuring individual and temporal variations in walking accessibility","volume":"106","author":"Willberg","year":"2023","journal-title":"J. Transp. Geogr."},{"key":"ref_45","first-page":"1785","article-title":"A framework for identifying activity groups from individual trajectories","volume":"57","author":"Shen","year":"2016","journal-title":"J. Transp. Geogr."},{"key":"ref_46","first-page":"144","article-title":"Urban activity location detection using cellular network data","volume":"52","author":"Wang","year":"2015","journal-title":"Transp. Res. Part C Emerg. Technol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"4507","DOI":"10.1038\/s41467-024-48909-7","article-title":"Unravelling the spatial directionality of urban mobility","volume":"15","author":"Zhao","year":"2024","journal-title":"Nat. Commun."},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Starczewski, A., Goetzen, P., and Er, M.J. (2020). A new method for automatic determining of the DBSCAN parameters. J. Artif. Intell. Soft Comput. Res., 10.","DOI":"10.2478\/jaiscr-2020-0014"},{"key":"ref_49","unstructured":"(2020, December 31). Shenzhen Statistical Yearbook 2020, Available online: https:\/\/tjj.sz.gov.cn\/attachment\/1\/1382\/1382787\/8386382.pdf."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"661","DOI":"10.1137\/070710111","article-title":"Power-Law Distributions in Empirical Data","volume":"51","author":"Clauset","year":"2009","journal-title":"SIAM Rev."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1038\/nature06958","article-title":"Understanding individual human mobility patterns","volume":"453","author":"Gonzalez","year":"2008","journal-title":"Nature"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1038\/s41562-018-0364-x","article-title":"Evidence for a conserved quantity in human mobility","volume":"2","author":"Alessandretti","year":"2018","journal-title":"Nat. Hum. Behav."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"9136","DOI":"10.1038\/srep09136","article-title":"Explaining the power-law distribution of human mobility through transportation modality decomposition","volume":"5","author":"Zhao","year":"2015","journal-title":"Sci. Rep."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1877","DOI":"10.1109\/LCOMM.2013.090213.130924","article-title":"Human mobility patterns in cellular networks","volume":"17","author":"Zhou","year":"2013","journal-title":"IEEE Commun. Lett."},{"key":"ref_55","doi-asserted-by":"crossref","unstructured":"Alessandretti, L., Sapiezynski, P., Lehmann, S., and Baronchelli, A. (2017). Multi-scale spatiotemporal analysis of human mobility. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0171686"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"958","DOI":"10.1080\/00045608.2012.687349","article-title":"The uncertain geographic context problem","volume":"102","author":"Kwan","year":"2012","journal-title":"Ann. Assoc. Am. Geogr."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1007\/s11116-013-9462-9","article-title":"How do built-environment factors affect travel behavior? A spatial analysis at different geographic scales","volume":"41","author":"Hong","year":"2014","journal-title":"Transportation"},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Park, Y.M., and Kwan, M.P. (2017). Multi-contextual segregation and environmental justice research: Toward fine-scale spatiotemporal approaches. Int. J. Environ. Res. Public Health, 14.","DOI":"10.3390\/ijerph14101205"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.habitatint.2015.08.038","article-title":"Daily life circle reconstruction: A scheme for sustainable development in urban China","volume":"50","author":"Liu","year":"2015","journal-title":"Habitat Int."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1247","DOI":"10.1016\/S1473-3099(20)30553-3","article-title":"Association between mobility patterns and COVID-19 transmission in the USA: A mathematical modelling study","volume":"20","author":"Badr","year":"2020","journal-title":"Lancet Infect. Dis."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"2190","DOI":"10.1109\/TMC.2018.2870135","article-title":"Spatio-temporal analysis and prediction of cellular traffic in metropolis","volume":"18","author":"Wang","year":"2018","journal-title":"IEEE Trans. Mob. Comput."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"4633","DOI":"10.1038\/s41467-021-24899-8","article-title":"Mobility patterns are associated with experienced income segregation in large US cities","volume":"12","author":"Moro","year":"2021","journal-title":"Nat. Commun."}],"container-title":["ISPRS International Journal of Geo-Information"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2220-9964\/15\/2\/56\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T13:03:54Z","timestamp":1769432634000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2220-9964\/15\/2\/56"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,26]]},"references-count":62,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["ijgi15020056"],"URL":"https:\/\/doi.org\/10.3390\/ijgi15020056","relation":{},"ISSN":["2220-9964"],"issn-type":[{"value":"2220-9964","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,26]]}}}