{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:54:54Z","timestamp":1760230494461,"version":"build-2065373602"},"reference-count":60,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,27]],"date-time":"2022-07-27T00:00:00Z","timestamp":1658880000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Slovenian Research Agency","award":["P2-0016","J2-2507"],"award-info":[{"award-number":["P2-0016","J2-2507"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The integration of infectious disease modeling with the data collection process is crucial to reach its maximum potential, and remains a significant research challenge. Ensuring a solid empirical foundation for models used to fill gaps in data and knowledge is of paramount importance. Personal wireless devices, such as smartphones, smartwatches and wireless bracelets, can serve as a means of bridging the gap between empirical data and the mathematical modeling of human contacts and networking. In this paper, we develop, implement, and evaluate concepts and architectures for advanced user-centric proximity estimation based on smartphone radio environment monitoring. We investigate innovative methods for the estimation of proximity, based on a person-radio-environment trace recorded by the smartphone, and define the proximity parameter. For this purpose, we developed a smartphone application and back-end services. The results show that, with the proposed procedure, we can estimate the proximity of two devices in terms of near, medium, and far distance with reasonable accuracy in real-world case scenarios.<\/jats:p>","DOI":"10.3390\/s22155609","type":"journal-article","created":{"date-parts":[[2022,7,28]],"date-time":"2022-07-28T03:21:16Z","timestamp":1658978476000},"page":"5609","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["User-Centric Proximity Estimation Using Smartphone Radio Fingerprinting"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5155-7672","authenticated-orcid":false,"given":"Ale\u0161","family":"\u0160vigelj","sequence":"first","affiliation":[{"name":"Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School (IPS), Jamova cesta 39, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5220-875X","authenticated-orcid":false,"given":"Andrej","family":"Hrovat","sequence":"additional","affiliation":[{"name":"Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School (IPS), Jamova cesta 39, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8676-5658","authenticated-orcid":false,"given":"Toma\u017e","family":"Javornik","sequence":"additional","affiliation":[{"name":"Jo\u017eef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia"},{"name":"Jo\u017eef Stefan International Postgraduate School (IPS), Jamova cesta 39, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1016\/j.epidem.2014.12.002","article-title":"Seven challenges for model-driven data collection in experimental and observational studies","volume":"10","author":"Lessler","year":"2015","journal-title":"Epidemics"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.epidem.2014.08.006","article-title":"Six challenges in measuring contact networks for use in modeling","volume":"10","author":"Eames","year":"2015","journal-title":"Epidemics"},{"key":"ref_3","unstructured":"Agrawal, A., Gans, J., Goldarb, A., and Lederman, M. 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