{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:17:23Z","timestamp":1760239043261,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,9,12]],"date-time":"2020-09-12T00:00:00Z","timestamp":1599868800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>In this article, we established new results related to a 2-pre-Hilbert space. Among these results we will mention the Cauchy-Schwarz inequality. We show several applications related to some statistical indicators as average, variance and standard deviation and correlation coefficient, using the standard 2-inner product and some of its properties. We also present a brief characterization of a linear regression model for the random variables in discrete case.<\/jats:p>","DOI":"10.3390\/sym12091501","type":"journal-article","created":{"date-parts":[[2020,9,13]],"date-time":"2020-09-13T22:01:01Z","timestamp":1600034461000},"page":"1501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Types of Statistical Indicators Characterized by 2-Pre-Hilbert Spaces"],"prefix":"10.3390","volume":"12","author":[{"given":"Nicu\u015for","family":"Minculete","sequence":"first","affiliation":[{"name":"Department of Mathematics and Computer Science, Transilvania University of Bra\u015fov, Iuliu Maniu Street, No. 50, 500091 Bra\u015fov, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,12]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"Lineare 2-normierte R\u00e4ume","volume":"28","year":"1965","journal-title":"Math. 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