{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T14:58:11Z","timestamp":1776783491898,"version":"3.51.2"},"reference-count":20,"publisher":"Springer Science and Business Media LLC","issue":"2","license":[{"start":{"date-parts":[[2024,11,16]],"date-time":"2024-11-16T00:00:00Z","timestamp":1731715200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2024,11,16]],"date-time":"2024-11-16T00:00:00Z","timestamp":1731715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"National Institute for Theoretical and Computational Sciences"},{"name":"Centre for Artificial Intelligence Research"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Quantum Mach. Intell."],"published-print":{"date-parts":[[2024,12]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>The quantum asymptotically universal multi-feature (QAUM) encoding architecture was recently introduced and showed improved expressivity and performance in classifying pulsar stars. The circuit uses generalized trainable layers of parameterized single-qubit rotation gates and single-qubit feature encoding gates. Although the improvement in classification accuracy is promising, the single-qubit nature of this architecture, combined with the circuit depth required for accuracy, limits its applications on NISQ devices due to their low coherence times. This work reports on the design, implementation, and evaluation of ensembles of single-qubit QAUM classifiers using classical bagging and boosting techniques. We demonstrate an improvement in validation accuracy for pulsar star classification. We find that this improvement is not dataset specific as we observe consistent improvements for the MNIST Digits and Wisconsin Cancer datasets. We also observe that the boosting ensemble achieves an acceptable level of accuracy with only a small amount of training, while the bagging ensemble achieves higher overall accuracy with ample training time. This shows that classical ensembles of single-qubit circuits present a new approach for certain classification problems.<\/jats:p>","DOI":"10.1007\/s42484-024-00211-x","type":"journal-article","created":{"date-parts":[[2024,11,16]],"date-time":"2024-11-16T04:23:46Z","timestamp":1731731026000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Classical ensembles of single-qubit quantum variational circuits for classification"],"prefix":"10.1007","volume":"6","author":[{"given":"Shane","family":"McFarthing","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anban","family":"Pillay","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ilya","family":"Sinayskiy","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesco","family":"Petruccione","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2024,11,16]]},"reference":[{"key":"211_CR1","doi-asserted-by":"publisher","unstructured":"Bezanson J, Edelman A, Karpinski S et al (2017) Julia: a fresh approach to numerical computing. 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Quantum 4:341 https:\/\/doi.org\/10.22331\/q-2020-10-11-341","DOI":"10.22331\/q-2020-10-11-341"},{"key":"211_CR9","doi-asserted-by":"publisher","unstructured":"Lyon RJ, Stappers B, Cooper S et al (2016) Fifty years of pulsar candidate selection: from simple filters to a new principled real-time classification approach. Month Notice Royal Astronom Soc 459(1):1104\u20131123. https:\/\/doi.org\/10.1093\/mnras\/stw656","DOI":"10.1093\/mnras\/stw656"},{"key":"211_CR10","doi-asserted-by":"publisher","unstructured":"Macaluso A, Clissa L, Lodi S, et\u00a0al. (2020) Quantum ensemble for classification. https:\/\/doi.org\/10.48550\/arXiv.2007.01028","DOI":"10.48550\/arXiv.2007.01028"},{"issue":"1","key":"211_CR11","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1038\/s41467-018-07090-4","volume":"9","author":"JR McClean","year":"2018","unstructured":"McClean JR, Boixo S, Smelyanskiy VN et al (2018) Barren plateaus in quantum neural network training landscapes. 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The authors declare no other competing interests.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing Interests"}}],"article-number":"81"}}