RESEARCH

Journal articles

• I Ktena*, O Wiles*, I Albuquerque, SA Rebuffi, R Tanno, A Guha Roy, S Azizi, D Belgrave, P Kohli, T Cemgil, A Karthikesalingam, S Gowal. "Generative models improve fairness of medical classifiers under distribution shifts". Nature Medicine, 2024. [link]

• I Gabriel, A Manzini, G Keeling, LA Hendricks, V Rieser, H Iqbal, N Tomašev, I Ktena, et al. "The Ethics of Advanced AI Assistants", 2024. [link]

• F Huszár*, SI Ktena*, C O’Brien*, L Belli, A Schlaikjer, M Hardt. "Algorithmic amplification of politics on Twitter". Proceedings of the National Academy of Sciences, 2022. [link]

• MD Schirmer, SI Ktena, MJ Nardin, K Donahue, AK Giese, M Etherton, O Wu, N Rost. "Rich-club organization: an important determinant of functional outcome after acute ischemic stroke". Frontiers in Neurology, 2019. [link]

• SI Ktena*, MD Schirmer*, M Etherton, AK Giese, C Tuozzo, B Mills, D Rueckert, O Wu, N Rost. "Brain connectivity measures improve modeling of functional outcome after acute ischemic stroke". Stroke, 2019. [link]

• S Parisot*, SI Ktena*, E Ferrante, M Lee, R Guerrerro Moreno, B Glocker, D Rueckert. "Disease Prediction using Graph Convolutional Networks: Application to Autism Spectrum Disorder and Alzheimer's Disease". Medical Image Analysis, 2018. [link]

• SI Ktena, S Parisot, E Ferrante, M Rajchl, M Lee, B Glocker, D Rueckert. "Metric Learning with Spectral Graph Convolutions on Brain Connectivity Networks". Neuroimage, 2018. [link]

• S Parisot, B Glocker, SI Ktena, S Arslan, MD Schirmer, S Arslan, D Rueckert.  "A flexible graphical model for multi-modal parcellation of the cortex". Neuroimage, 2017. [link]

• S Arslan, SI Ktena, A Makropoulos, E Robinson, D Rueckert, S Parisot. "Human Brain Mapping: A Systematic Comparison of Parcellation Methods for the Human Cerebral Cortex". Neuroimage, 2017. [link]

*equal contribution

Conference articles

• A Velingker, AK Sinop, I Ktena, P Veličković, S Gollapudi. "Affinity-Aware Graph Networks", NeurIPS, December 2023. [link] 

• V Aglietti, A Malek, I Ktena, S Chiappa. "Constrained causal bayesian optimization", ICML, July 2023. [link]

• F Ribeiro, V Shumovskaia, T Davies, I Ktena. "How fair is your graph? Exploring fairness concerns in neuroimaging studies", Machine Learning for Healthcare, August, 2022.

• O Wiles, S Gowal, F Stimberg, S Alvise-Rebuffi, SI Ktena, T Cemgil. "A Fine-Grained Analysis on Distribution Shift", ICLR, April 2022. (Oral Presentation)

• D Guo, SI Ktena, F Huszar, P Kumar Myana, W Shi, A Tejani. "Deep Bayesian Bandits: Exploring in Online Personalized Recommendations", RecSsys, September 2020.

• C Zhang, Y Liu, Y Xie, SI Ktena, A Tejani, A Gupta, P Kumar Myana, D Dilipkumar, S Paul, I Ihara, P Upadhyaya, F Huszar, W Shi. "Model Size Reduction Using Frequency Based Double Hashing for Recommender Systems", RecSys, September 2020. 

• SI Ktena, A Tejani, L Theis, P Kumar Myana, D Dilipkumar, F Huszar, S Yoo, W Shi. "Addressing Delayed Feedback for Continuous Training with Neural Networks in CTR prediction", RecSys, Copenhagen, September 2019. (Oral Presentation) [link]

• SI Ktena, S Parisot, E Ferrante, M Rajchl, M Lee, B Glocker, D Rueckert. "Distance Metric Learning using Graph Convolutional Networks: Application to Functional Brain Networks". MICCAI, Quebec City, September 2017. [link][code]

• S Parisot, SI Ktena, E Ferrante, M Lee, R Guerrerro Moreno, B Glocker, D Rueckert. "Spectral Graph Convolutions for Population-based Disease Prediction". MICCAI, Quebec City, September 2017. [link][code]

• SI Ktena, S Arslan, S Parisot, D Rueckert. "Exploring Heritability of Functional Brain Networks with Inexact Graph Matching". ISBI, Melbourne, April 2017. (Oral Presentation) [pdf]

• SI Ktena, W Abbott, AA Faisal. "A virtual reality platform for safe evaluation and training of natural gaze-based wheelchair driving". 7th International IEEE/EMBS Conference on Neural Engineering (NER), Montpellier, April 2015. (Oral Presentation) [pdf][slides]

Preprints

• L Yang, S Xu, A Sellergren, T Kohlberger, Y Zhou, I Ktena, A Kiraly,  et al. "Advancing Multimodal Medical Capabilities of Gemini", arXiv:2405.03162 [pdf]

• S Ghalebikesabi, L Berrada, S Gowal, I Ktena, R Stanforth, J Hayes, S De, SL Smith, O Wiles, B Balle. "Differentially Private Diffusion Models Generate Useful Synthetic Images", arXiv:2302.13861 [pdf]

• N Sonnerat, P Wang, I Ktena, S Bartunov, V Nair. "Learning a Large Neighborhood Search Algorithm for Mixed Integer Programs", arXiv:2107.10201 [pdf]

• V Nair, S Bartunov, F Gimeno, I von Glehn, P Lichocki, I Lobov, B O'Donoghue, N Sonnerat, C Tjandraatmadja, P Wang, R Addanki, T Hapuarachchi, T Keck, J Keeling, P Kohli, SI Ktena, Y Li, O Vinyals, Y Zwols. "Solving Mixed Integer Programs Using Neural Networks", arXiv:2012.13349 [pdf]

• L Belli, SI Ktena, A Tejani, A Lung-Yut-Fon, F Portman, X Zhu, Y Xie, A Gupta, M Bronstein, A Delić, G Sottocornola, W Anelli, N Andrade, J Smith, W Shi. "Privacy-Preserving Recommender Systems Challenge on Twitter's Home Timeline", arXiv:2004.13715 [pdf]

Theses

• "Computational Analysis and Modelling of Graph-Structured Neuroimaging Data", PhD in Medical Image Computing, August 2018, Imperial College London.

• "Computational Analysis and Modelling of Functional Brain Networks",  Master of Research (MRes) in Advanced Computing, September 2015, Imperial College London.

• "Eye-based wheelchair navigation: A virtual reality platform", Master of Science (MSc) in Biomedical Engineering, September 2013, Imperial College London.