publications | Conor B. Hamill

2024

arXiv
A Brief Review of Quantum Machine Learning for Financial Services

Mina Doosti , Petros Wallden , Conor Brian Hamill , and 3 more authors

2024

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This review paper examines state-of-the-art algorithms and techniques in quantum machine learning with potential applications in finance. We discuss QML techniques in supervised learning tasks, such as Quantum Variational Classifiers, Quantum Kernel Estimation, and Quantum Neural Networks (QNNs), along with quantum generative AI techniques like Quantum Transformers and Quantum Graph Neural Networks (QGNNs). The financial applications considered include risk management, credit scoring, fraud detection, and stock price prediction. We also provide an overview of the challenges, potential, and limitations of QML, both in these specific areas and more broadly across the field. We hope that this can serve as a quick guide for data scientists, professionals in the financial sector, and enthusiasts in this area to understand why quantum computing and QML in particular could be interesting to explore in their field of expertise.
@misc{doosti2024briefreviewquantummachine, title = {A Brief Review of Quantum Machine Learning for Financial Services}, author = {Doosti, Mina and Wallden, Petros and Hamill, Conor Brian and Hankache, Robert and Brown, Oliver Thomson and Heunen, Chris}, year = {2024}, eprint = {2407.12618}, archiveprefix = {arXiv}, primaryclass = {quant-ph}, }

2023

arXiv
Agent-based Modelling of Credit Card Promotions

Conor B. Hamill , Raad Khraishi , Simona Gherghel , and 4 more authors

arXiv e-prints, Nov 2023

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Interest-free promotions are a prevalent strategy employed by credit card lenders to attract new customers, yet the research exploring their effects on both consumers and lenders remains relatively sparse. The process of selecting an optimal promotion strategy is intricate, involving the determination of an interest-free period duration and promotion-availability window, all within the context of competing offers, fluctuating market dynamics, and complex consumer behaviour. In this paper, we introduce an agent-based model that facilitates the exploration of various credit card promotions under diverse market scenarios. Our approach, distinct from previous agent-based models, concentrates on optimising promotion strategies and is calibrated using benchmarks from the UK credit card market from 2019 to 2020, with agent properties derived from historical distributions of the UK population from roughly the same period. We validate our model against stylised facts and time-series data, thereby demonstrating the value of this technique for investigating pricing strategies and understanding credit card customer behaviour. Our experiments reveal that, in the absence of competitor promotions, lender profit is maximised by an interest-free duration of approximately 12 months while market share is maximised by offering the longest duration possible. When competitors do not offer promotions, extended promotion availability windows yield maximum profit for lenders while also maximising market share. In the context of concurrent interest-free promotions, we identify that the optimal lender strategy entails offering a more competitive interest-free period and a rapid response to competing promotional offers. Notably, a delay of three months in responding to a rival promotion corresponds to a 2.4% relative decline in income.
@article{2023arXiv231101901H, author = {Hamill, Conor B. and Khraishi, Raad and Gherghel, Simona and Lawrence, Jerrard and Mercuri, Salvatore and Okhrati, Ramin and Cowan, Greig A.}, title = {{Agent-based Modelling of Credit Card Promotions}}, journal = {arXiv e-prints}, keywords = {Computer Science - Multiagent Systems, Economics - General Economics}, year = {2023}, month = nov, eid = {arXiv:2311.01901}, pages = {arXiv:2311.01901}, doi = {10.48550/arXiv.2311.01901}, archiveprefix = {arXiv}, eprint = {2311.01901}, primaryclass = {cs.MA}, adsurl = {https://ui.adsabs.harvard.edu/abs/2023arXiv231101901H}, adsnote = {Provided by the SAO/NASA Astrophysics Data System}, }

EPJConf

RIB induced reactions: Studying astrophysical reactions with low-energy RI beam at CRIB

H. Yamaguchi , S. Hayakawa , N.R. Ma , and 60 more authors

EPJ Web of Conferences, Nov 2023

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@article{Yamaguchi2023,
  title = {RIB induced reactions: Studying astrophysical reactions with low-energy RI beam at CRIB},
  volume = {275},
  issn = {2100-014X},
  url = {http://dx.doi.org/10.1051/epjconf/202327501015},
  doi = {10.1051/epjconf/202327501015},
  journal = {EPJ Web of Conferences},
  publisher = {EDP Sciences},
  author = {Yamaguchi, H. and Hayakawa, S. and Ma, N.R. and Shimizu, H. and Okawa, K. and Zhang, Q. and Yang, L. and Kahl, D. and La Cognata, M. and Lamia, L. and Abe, K. and Beliuskina, O. and Cha, S.M. and Chae, K.Y. and Cherubini, S. and Figuera, P. and Ge, Z. and Gulino, M. and Hu, J. and Inoue, A. and Iwasa, N. and Kim, A. and Kim, D. and Kiss, G. and Kubono, S. and La Commara, M. and Lattuada, M. and Lee, E.J. and Moon, J.Y. and Palmerini, S. and Parascandolo, C. and Park, S.Y. and Phong, V.H. and Pierroutsakou, D. and Pizzone, R.G. and Rapisarda, G.G. and Romano, S. and Spitaleri, C. and Tang, X.D. and Trippella, O. and Tumino, A. and Zhang, N.T. and Lam, Y.H. and Heger, A. and Jacobs, A.M. and Xu, S.W. and Ma, S.B. and Ru, L.H. and Liu, E.Q. and Liu, T. and Hamill, C.B. and Murphy, A. St J. and Su, J. and Fang, X. and Kwag, M.S. and Duy, N.N. and Uyen, N.K. and Kim, D.H. and Liang, J. and Psaltis, A. and Sferrazza, M. and Johnston, Z. and Li, Y.Y.},
  editor = {Lamia, L. and Pizzone, R.G. and Rapisarda, G.G. and Sergi, M.L.},
  year = {2023},
  pages = {01015},
}

2022

EPJConf

First measurement of 25Al+p resonant scattering relevant to the astrophysical reaction 22Mg(α, p)25Al

J. Hu , H. Yamaguchi , Y.H. Lam , and 34 more authors

EPJ Web of Conferences, Nov 2022

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@article{Hu2022,
  title = {First measurement of 25Al+p resonant scattering relevant to the astrophysical reaction 22Mg(α, p)25Al},
  volume = {260},
  issn = {2100-014X},
  url = {http://dx.doi.org/10.1051/epjconf/202226005001},
  doi = {10.1051/epjconf/202226005001},
  journal = {EPJ Web of Conferences},
  publisher = {EDP Sciences},
  author = {Hu, J. and Yamaguchi, H. and Lam, Y.H. and Heger, A. and Kahl, D. and Jacobs, A.M. and Johnston, Z. and Xu, S.W. and Zhang, N.T. and Ma, S.B. and Ru, L.H. and Liu, E.Q. and Liu, T. and Hayakawa, S. and Yang, L. and Shimizu, H. and Hamill, C.B. and Murphy, A. StJ. and Su, J. and Fang, X. and Chae, K.Y. and Kwag, M.S. and Cha, S.M. and Duy, N.N. and Uyen, N.K. and Kim, D.H. and Pizzone, R.G. and La Cognata, M. and Cherubini, S. and Romano, S. and Tumino, A. and Liang, J. and Psaltis, A. and Sferrazza, M. and Kim, D. and Li, Y.Y. and Kubono, S.},
  editor = {Liu, W. and Wang, Y. and Guo, B. and Tang, X. and Zeng, S.},
  year = {2022},
  pages = {05001},
}

EPJConf

Experimental studies on astrophysical reactions at the low-energy RI beam separator CRIB

H. Yamaguchi , S. Hayakawa , N.R. Ma , and 59 more authors

EPJ Web of Conferences, Nov 2022

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@article{Yamaguchi2022,
  title = {Experimental studies on astrophysical reactions at the low-energy RI beam separator CRIB},
  volume = {260},
  issn = {2100-014X},
  url = {http://dx.doi.org/10.1051/epjconf/202226003003},
  doi = {10.1051/epjconf/202226003003},
  journal = {EPJ Web of Conferences},
  publisher = {EDP Sciences},
  author = {Yamaguchi, H. and Hayakawa, S. and Ma, N.R. and Shimizu, H. and Okawa, K. and Yang, L. and Kahl, D. and La Cognata, M. and Lamia, L. and Abe, K. and Beliuskina, O. and Cha, S.M. and Chae, K.Y. and Cherubini, S. and Figuera, P. and Ge, Z. and Gulino, M. and Hu, J. and Inoue, A. and Iwasa, N. and Kim, A. and Kim, D. and Kiss, G. and Kubono, S. and La Commara, M. and Lattuada, M. and Lee, E.J. and Moon, J.Y. and Palmerini, S. and Parascandolo, C. and Park, S.Y. and Phong, V. H. and Pierroutsakou, D. and Pizzone, R.G. and Rapisarda, G.G. and Romano, S. and Spitaleri, C. and Tang, X.D. and Trippella, O. and Tumino, A. and Zhang, N.T. and Lam, Y.H. and Heger, A. and Jacobs, A.M. and Xu, S.W. and Ma, S.B. and Ru, L.H. and Liu, E.Q. and Liu, T. and Hamill, C.B. and St J. Murphy, A. and Su, J. and Fang, X. and Kwag, M.S. and Duy, N.N. and Uyen, N.K. and Kim, D.H. and Liang, J and Psaltis, A. and Sferrazza, M. and Johnston, Z. and Li, Y.Y.},
  editor = {Liu, W. and Wang, Y. and Guo, B. and Tang, X. and Zeng, S.},
  year = {2022},
  pages = {03003},
}

arXiv
An Introduction to Machine Unlearning

Salvatore Mercuri , Raad Khraishi , Ramin Okhrati , and 4 more authors

arXiv e-prints, Sep 2022

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Removing the influence of a specified subset of training data from a machine learning model may be required to address issues such as privacy, fairness, and data quality. Retraining the model from scratch on the remaining data after removal of the subset is an effective but often infeasible option, due to its computational expense. The past few years have therefore seen several novel approaches towards efficient removal, forming the field of "machine unlearning", however, many aspects of the literature published thus far are disparate and lack consensus. In this paper, we summarise and compare seven state-of-the-art machine unlearning algorithms, consolidate definitions of core concepts used in the field, reconcile different approaches for evaluating algorithms, and discuss issues related to applying machine unlearning in practice.
@article{2022arXiv220900939M, author = {Mercuri, Salvatore and Khraishi, Raad and Okhrati, Ramin and Batra, Devesh and Hamill, Conor and Ghasempour, Taha and Nowlan, Andrew}, title = {{An Introduction to Machine Unlearning}}, journal = {arXiv e-prints}, keywords = {Computer Science - Machine Learning}, year = {2022}, month = sep, eid = {arXiv:2209.00939}, pages = {arXiv:2209.00939}, doi = {10.48550/arXiv.2209.00939}, archiveprefix = {arXiv}, eprint = {2209.00939}, primaryclass = {cs.LG}, adsurl = {https://ui.adsabs.harvard.edu/abs/2022arXiv220900939M}, adsnote = {Provided by the SAO/NASA Astrophysics Data System}, }

2021

PhysRevLett

Advancement of Photospheric Radius Expansion and Clocked Type-I X-Ray Burst Models with the New Mg22(α, p)Al25 Reaction Rate Determined at the Gamow Energy

J. Hu , H. Yamaguchi , Y. H. Lam , and 34 more authors

Physical Review Letters, Oct 2021

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@article{Hu2021,
  title = {Advancement of Photospheric Radius Expansion and Clocked Type-I X-Ray Burst Models with the New
  <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mrow><mml:mmultiscripts><mml:mrow><mml:mi>Mg</mml:mi></mml:mrow><mml:mprescripts /><mml:none /><mml:mrow><mml:mn>22</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mi>α</mml:mi><mml:mo>, </mml:mo><mml:mi>p</mml:mi><mml:mo stretchy="false">)</mml:mo><mml:mmultiscripts><mml:mrow><mml:mi>Al</mml:mi></mml:mrow><mml:mprescripts /><mml:none /><mml:mrow><mml:mn>25</mml:mn></mml:mrow></mml:mmultiscripts></mml:mrow></mml:math>
   Reaction Rate Determined at the Gamow Energy},
  volume = {127},
  issn = {1079-7114},
  url = {http://dx.doi.org/10.1103/PhysRevLett.127.172701},
  doi = {10.1103/physrevlett.127.172701},
  number = {17},
  journal = {Physical Review Letters},
  publisher = {American Physical Society (APS)},
  author = {Hu, J. and Yamaguchi, H. and Lam, Y. H. and Heger, A. and Kahl, D. and Jacobs, A. M. and Johnston, Z. and Xu, S. W. and Zhang, N. T. and Ma, S. B. and Ru, L. H. and Liu, E. Q. and Liu, T. and Hayakawa, S. and Yang, L. and Shimizu, H. and Hamill, C. B. and Murphy, A. St J. and Su, J. and Fang, X. and Chae, K. Y. and Kwag, M. S. and Cha, S. M. and Duy, N. N. and Uyen, N. K. and Kim, D. H. and Pizzone, R. G. and La Cognata, M. and Cherubini, S. and Romano, S. and Tumino, A. and Liang, J. and Psaltis, A. and Sferrazza, M. and Kim, D. and Li, Y. Y. and Kubono, S.},
  year = {2021},
  month = oct,
}

Measurement of the 25Mg(d, p)26Mg reaction to constrain nucleosynthesis in novae and the weak s-process

Conor Brian Hamill

Oct 2021

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The 25Al(p, γ) 26Si reaction rate is one of the few outstanding uncertainties in modelling the contribution from novae to the galactic budget of the long-lived radioactive isotope 26Al. The rate is dominated by three key resonances in 26Si (J π = 1+, 0+ and 3+), of which only the 3+ resonance has been directly constrained. The first experiment described in this thesis used the 25Mg(d, p) reaction to measure the spectroscopic factors of the three analog states in the mirror nucleus 26Mg, including a spectroscopic factor for the 0+ state. The proton partial widths estimated from these spectroscopic factors established the 0+ state contributes .10% of the 25Al(p, γ) reaction rate, with the 3+ state dominating at higher temperatures. The upper limit extracted for the 1+ proton partial width, which disagreed with a previous (4He, 3He) study, found it only contributes to the reaction rate at low temperatures. Previous studies presented evidence for a negative parity state in 26Mg around 5.7 MeV, consistent with the angular distribution measured in the current work, which has not had an analog state in 26Si confirmed. Future work should focus on identifying such a state and further constraining the parameters of the dominant 3+ resonance. The amount of neutrons available for the weak s-process depends on the 22Ne(α, n) and 22Ne(α, γ) reaction rates, which proceed through natural-parity states of 26Mg above the alpha and neutron thresholds. The second experiment in this thesis used the 25Mg(d, p) reaction to populate states above the 26Mg alpha threshold. The shapes of the angular distributions constrained the ‘-transfers populating those states. This established the spin/parities of states at 10.82, 10.95, 11.08 and 11.11 MeV as 2+, 1−, 2+ and 2+ respectively. Combining these assignments with previous alpha-transfer studies allowed alpha partial widths to be extracted, which were used to calculate reaction rates for both reactions. Studies seeking to further reduce these rate uncertainties should focus on constraining the properties of the 10.95 and 11.11 MeV states, which dominate the reactions at temperatures whenever the 22Ne(α, n) rate overtakes that of the 22Ne(α, γ) reaction.
@phdthesis{Hamill2021, title = {Measurement of the 25Mg(d, p)26Mg reaction to constrain nucleosynthesis in novae and the weak s-process}, author = {Hamill, Conor Brian}, year = {2021}, url = {https://era.ed.ac.uk/handle/1842/38582}, school = {University of Edinburgh}, type = {PhD thesis}, }

2020

EPJA

Study of the 25Mg(d, p)26Mg reaction to constrain the 25Al(p, γ)26Si resonant reaction rates in nova burning conditions

C. B. Hamill , P. J. Woods , D. Kahl , and 5 more authors

The European Physical Journal A, Feb 2020

Bib HTML

@article{Hamill2020,
  title = {Study of the 25Mg(d, p)26Mg reaction to constrain the 25Al(p, ${\gamma }$)26Si resonant reaction rates in nova burning conditions},
  volume = {56},
  issn = {1434-601X},
  url = {http://dx.doi.org/10.1140/epja/s10050-020-00052-9},
  doi = {10.1140/epja/s10050-020-00052-9},
  number = {2},
  journal = {The European Physical Journal A},
  publisher = {Springer Science and Business Media LLC},
  author = {Hamill, C. B. and Woods, P. J. and Kahl, D. and Longland, R. and Greene, J. P. and Marshall, C. and Portillo, F. and Setoodehnia, K.},
  year = {2020},
  month = feb,
  dimensions = {true},
}

2018

PhysRevC

High-statistics measurement of the η→3π0 decay at the Mainz Microtron

S. Prakhov , S. Abt , P. Achenbach , and 86 more authors

Physical Review C, Jun 2018

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@article{Prakhov2018,
  title = {High-statistics measurement of the
  <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>η</mml:mi><mml:mo>→</mml:mo><mml:mn>3</mml:mn><mml:msup><mml:mi>π</mml:mi><mml:mn>0</mml:mn></mml:msup></mml:mrow></mml:math>
   decay at the Mainz Microtron},
  volume = {97},
  issn = {2469-9993},
  url = {http://dx.doi.org/10.1103/PhysRevC.97.065203},
  doi = {10.1103/physrevc.97.065203},
  number = {6},
  journal = {Physical Review C},
  publisher = {American Physical Society (APS)},
  author = {Prakhov, S. and Abt, S. and Achenbach, P. and Adlarson, P. and Afzal, F. and Aguar-Bartolomé, P. and Ahmed, Z. and Ahrens, J. and Annand, J. R. M. and Arends, H. J. and Bantawa, K. and Bashkanov, M. and Beck, R. and Biroth, M. and Borisov, N. S. and Braghieri, A. and Briscoe, W. J. and Cherepnya, S. and Cividini, F. and Collicott, C. and Costanza, S. and Denig, A. and Dieterle, M. and Downie, E. J. and Drexler, P. and Ferretti Bondy, M. I. and Fil’kov, L. V. and Fix, A. and Gardner, S. and Garni, S. and Glazier, D. I. and Gorodnov, I. and Gradl, W. and Gurevich, G. M. and Hamill, C. B. and Heijkenskj\"{o}ld, L. and Hornidge, D. and Huber, G. M. and K\"{a}ser, A. and Kashevarov, V. L. and Kay, S. and Keshelashvili, I. and Kondratiev, R. and Korolija, M. and Krusche, B. and Lazarev, A. and Lisin, V. and Livingston, K. and Lutterer, S. and MacGregor, I. J. D. and Manley, D. M. and Martel, P. P. and McGeorge, J. C. and Middleton, D. G. and Miskimen, R. and Mornacchi, E. and Mushkarenkov, A. and Neganov, A. and Neiser, A. and Oberle, M. and Ostrick, M. and Otte, P. B. and Paudyal, D. and Pedroni, P. and Polonski, A. and Ron, G. and Rostomyan, T. and Sarty, A. and Sfienti, C. and Sokhoyan, V. and Spieker, K. and Steffen, O. and Strakovsky, I. I. and Strandberg, B. and Strub, Th. and Supek, I. and Thiel, A. and Thiel, M. and Thomas, A. and Unverzagt, M. and Usov, Yu. A. and Wagner, S. and Walford, N. K. and Watts, D. P. and Werthm\"{u}ller, D. and Wettig, J. and Witthauer, L. and Wolfes, M. and Zana, L. A.},
  year = {2018},
  month = jun,
}

PhysRevC

Experimental study of the γp→π0ηp reaction with the A2 setup at the Mainz Microtron

V. Sokhoyan , S. Prakhov , A. Fix , and 87 more authors

Physical Review C, May 2018

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@article{Sokhoyan2018,
  title = {Experimental study of the
  <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>γ</mml:mi><mml:mi>p</mml:mi><mml:mo>→</mml:mo><mml:msup><mml:mi>π</mml:mi><mml:mn>0</mml:mn></mml:msup><mml:mi>η</mml:mi><mml:mi>p</mml:mi></mml:mrow></mml:math>
   reaction with the A2 setup at the Mainz Microtron},
  volume = {97},
  issn = {2469-9993},
  url = {http://dx.doi.org/10.1103/PhysRevC.97.055212},
  doi = {10.1103/physrevc.97.055212},
  number = {5},
  journal = {Physical Review C},
  publisher = {American Physical Society (APS)},
  author = {Sokhoyan, V. and Prakhov, S. and Fix, A. and Abt, S. and Achenbach, P. and Adlarson, P. and Afzal, F. and Aguar-Bartolomé, P. and Ahmed, Z. and Ahrens, J. and Annand, J. R. M. and Arends, H. J. and Bantawa, K. and Bashkanov, M. and Beck, R. and Biroth, M. and Borisov, N. S. and Braghieri, A. and Briscoe, W. J. and Cherepnya, S. and Cividini, F. and Collicott, C. and Costanza, S. and Denig, A. and Dieterle, M. and Downie, E. J. and Drexler, P. and Ferretti Bondy, M. I. and Fil’kov, L. V. and Gardner, S. and Garni, S. and Glazier, D. I. and Gorodnov, I. and Gradl, W. and G\"{u}nther, M. and Gurevich, G. M. and Hamill, C. B. and Heijkenskj\"{o}ld, L. and Hornidge, D. and Huber, G. M. and K\"{a}ser, A. and Kashevarov, V. L. and Kay, S. and Keshelashvili, I. and Kondratiev, R. and Korolija, M. and Krusche, B. and Lazarev, A. and Lisin, V. and Livingston, K. and Lutterer, S. and MacGregor, I. J. D. and Manley, D. M. and Martel, P. P. and McGeorge, J. C. and Middleton, D. G. and Miskimen, R. and Mornacchi, E. and Mushkarenkov, A. and Neganov, A. and Neiser, A. and Oberle, M. and Ostrick, M. and Otte, P. B. and Paudyal, D. and Pedroni, P. and Polonski, A. and Ron, G. and Rostomyan, T. and Sarty, A. and Sfienti, C. and Spieker, K. and Steffen, O. and Strakovsky, I. I. and Strandberg, B. and Strub, Th. and Supek, I. and Thiel, A. and Thiel, M. and Thomas, A. and Unverzagt, M. and Usov, Yu. A. and Wagner, S. and Walford, N. K. and Watts, D. P. and Werthm\"{u}ller, D. and Wettig, J. and Witthauer, L. and Wolfes, M. and Zana, L. A.},
  year = {2018},
  month = may,
}