{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:17:15Z","timestamp":1760059035639,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T00:00:00Z","timestamp":1747785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Culture and Innovation","award":["2022-2.1.1-NL-2022-00004"],"award-info":[{"award-number":["2022-2.1.1-NL-2022-00004"]}]},{"name":"Ministry of Innovation and Technology","award":["2022-2.1.1-NL-2022-00004"],"award-info":[{"award-number":["2022-2.1.1-NL-2022-00004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["MAKE"],"abstract":"<jats:p>We present a model of classical binary time series derived from a matrix product state (MPS) Ansatz widely used in one-dimensional quantum systems. We discuss how this quantum Ansatz allows us to generate classical time series in a sequential manner. Our time series are built in two steps: First, a lower-level series (the driving noise or the increments) is created directly from the MPS representation, which is then integrated to create our ultimate higher-level series. The lower- and higher-level series have clear interpretations in the quantum context, and we elaborate on this correspondence with specific examples such as the spin-1\/2 Ising model in a transverse field (ITF model), where spin configurations correspond to the increments of discrete-time, discrete-level stochastic processes with finite or infinite autocorrelation lengths, Gaussian or non-Gaussian limit distributions, nontrivial Hurst exponents, multifractality, asymptotic self-similarity, etc. Our time series model is a parametric model, and we investigate how flexible the model is in some synthetic and real-life calibration problems.<\/jats:p>","DOI":"10.3390\/make7020044","type":"journal-article","created":{"date-parts":[[2025,5,21]],"date-time":"2025-05-21T09:58:22Z","timestamp":1747821502000},"page":"44","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Quantum-Inspired Models for Classical Time Series"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7086-235X","authenticated-orcid":false,"given":"Zolt\u00e1n","family":"Udvarnoki","sequence":"first","affiliation":[{"name":"Department of Physics of Complex Systems, E\u00f6tv\u00f6s Lor\u00e1nd University, 1117 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G\u00e1bor","family":"F\u00e1th","sequence":"additional","affiliation":[{"name":"Department of Physics of Complex Systems, E\u00f6tv\u00f6s Lor\u00e1nd University, 1117 Budapest, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,21]]},"reference":[{"key":"ref_1","first-page":"427","article-title":"Distribution of the Estimators for Autoregressive Time Series With a Unit Root","volume":"74","author":"Dickey","year":"1979","journal-title":"J. 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