{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T06:52:27Z","timestamp":1777704747671,"version":"3.51.4"},"reference-count":18,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2019,1,9]],"date-time":"2019-01-09T00:00:00Z","timestamp":1546992000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Journal of Intelligent &amp; Fuzzy Systems"],"published-print":{"date-parts":[[2019,2,16]]},"abstract":"<jats:p>Covariance is a measure to characterize the joint variability of two complex uncertain variables. Since, calculating covariance is not easy based on uncertain measure, we present two formulas for covariance and pseudo covariance of complex uncertain variables. For calculating the covariance of complex uncertain variables, some theorems are proved and several formulas are provided by using the inverse uncertainty distribution. The main results are explained by using several examples.<\/jats:p>","DOI":"10.3233\/jifs-181233","type":"journal-article","created":{"date-parts":[[2019,1,11]],"date-time":"2019-01-11T11:36:18Z","timestamp":1547206578000},"page":"241-251","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":6,"title":["Covariance and Pseudo-Covariance of Complex Uncertain Variables"],"prefix":"10.1177","volume":"36","author":[{"given":"Rong","family":"Gao","sequence":"first","affiliation":[{"name":"School of Economics and Management, Hebei University of Technology, Tianjin, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hamed","family":"Ahmadzade","sequence":"additional","affiliation":[{"name":"Department of Mathematical Sciences, University of Sistan and Baluchestan, Zahedan, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mojtaba","family":"Esfahani","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Velayat University, Iranshahr, Iran"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2019,1,9]]},"reference":[{"issue":"2","key":"e_1_3_2_2_2","first-page":"1","article-title":"Some results of moments of uncertain random variables","volume":"14","author":"Ahmadzade H.","year":"2017","unstructured":"AhmadzadeH., ShengY.H. and HassantabarF., Some results of moments of uncertain random variables, Iranian Journal of Fuzzy Systems 14(2) (2017), 1\u201321.","journal-title":"Iranian Journal of Fuzzy Systems"},{"key":"e_1_3_2_3_2","doi-asserted-by":"publisher","DOI":"10.1007\/s10700-016-9242-z"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.3233\/JIFS-18080"},{"key":"e_1_3_2_5_2","doi-asserted-by":"publisher","DOI":"10.3233\/IFS-152083"},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-981-10-2920-2_31"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00500-017-2717-1"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.knosys.2016.07.006"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1109\/TFUZZ.2017.2724021"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1214\/aoms\/1177704250"},{"key":"e_1_3_2_11_2","unstructured":"LiuB. 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