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With the additional ingredient of a scheme by which the properties of one agent may influence another, we arrive at a flexible framework for treating multiple interacting quantum and classical Bayesian agents. We present simulations in several settings to illustrate our construction: quantum and classical agents receiving signals from an exogenous source, two interacting classical agents, two interacting quantum agents, and interactions between classical and quantum agents. A consistent treatment of multiple interacting users of quantum theory may allow us to properly interpret existing multi-agent protocols and could suggest new approaches in other areas such as quantum algorithm design.<\/jats:p>","DOI":"10.22331\/q-2022-05-16-713","type":"journal-article","created":{"date-parts":[[2022,5,16]],"date-time":"2022-05-16T14:01:42Z","timestamp":1652709702000},"page":"713","update-policy":"https:\/\/doi.org\/10.22331\/q-crossmark-policy-page","source":"Crossref","is-referenced-by-count":5,"title":["Quantum and Classical Bayesian Agents"],"prefix":"10.22331","volume":"6","author":[{"given":"John B.","family":"DeBrota","sequence":"first","affiliation":[{"name":"Department of Physics and Astronomy, Tufts University, Medford, MA 02155, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter J.","family":"Love","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"9598","published-online":{"date-parts":[[2022,5,16]]},"reference":[{"key":"0","doi-asserted-by":"publisher","unstructured":"Eugene P. 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