{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T13:54:17Z","timestamp":1777643657864,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,3,23]],"date-time":"2022-03-23T00:00:00Z","timestamp":1647993600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>Deep regression models are widely employed to solve computer vision tasks, such as human age or pose estimation, crowd counting, object detection, etc. Another possible area of application, which to our knowledge has not been systematically explored so far, is proportion judgment. As a prerequisite for successful decision making, individuals often have to use proportion judgment strategies, with which they estimate the magnitude of one stimulus relative to another (larger) stimulus. This makes this estimation problem interesting for the application of machine learning techniques. In regard to this, we proposed various deep regression architectures, which we tested on three original datasets of very different origin and composition. This is a novel approach, as the assumption is that the model can learn the concept of proportion without explicitly counting individual objects. With comprehensive experiments, we have demonstrated the effectiveness of the proposed models which can predict proportions on real-life datasets more reliably than human experts, considering the coefficient of determination (&gt;0.95) and the amount of errors (MAE &lt; 2, RMSE &lt; 3). If there is no significant number of errors in determining the ground truth, with an appropriate size of the learning dataset, an additional reduction of MAE to 0.14 can be achieved. The used datasets will be publicly available to serve as reference data sources in similar projects.<\/jats:p>","DOI":"10.3390\/fi14040100","type":"journal-article","created":{"date-parts":[[2022,3,23]],"date-time":"2022-03-23T12:20:25Z","timestamp":1648038025000},"page":"100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Deep Regression Neural Networks for Proportion Judgment"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8877-4689","authenticated-orcid":false,"given":"Mario","family":"Milicevic","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering and Computing, University of Dubrovnik, 20000 Dubrovnik, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vedran","family":"Batos","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computing, University of Dubrovnik, 20000 Dubrovnik, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9774-1080","authenticated-orcid":false,"given":"Adriana","family":"Lipovac","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Computing, University of Dubrovnik, 20000 Dubrovnik, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zeljka","family":"Car","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering and Computing, University of Zagreb, 10000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2781","DOI":"10.3758\/s13414-015-0974-6","article-title":"How to estimate how well people estimate: Evaluating measures of individual differences in the approximate number system","volume":"77","author":"Chesney","year":"2015","journal-title":"Atten. 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