Vasileios Kalantzis  Vasileios Kalantzis photo         

contact information

Research Staff Member
IBM Research USA, Thomas J. Watson Research Center


Professional Associations

Professional Associations:  ACM  |  Society for Industrial and Applied Mathematics


Directed Graph Transformers
Qitong Wang, Georgios Kollias, Theodoros Salonidids, Vassilis Kalantzis, Naoki Abe, Mohammed J. Zaki
Technical Report, 2022

Exponential advantage for topological data analysis on noisy quantum devices
Ismail Yunus Akhalwaya, Shashanka Ubaru, Kenneth L. Clarkson, Mark S. Squillante, Vishnu Jejjala, Yang-Hui He, Kugendran Naidoo, Vassilis Kalantzis, Lior Horesh
Technical Report, 2022

A Parallel Algorithm for Computing Partial Spectral Factorizations of Matrix Pencils via Chebyshev Approximation
Tianshi Xu, Anthony P. Austin, Vassilis Kalantzis, Yousef Saad
Technical Report, 2022

On Quantum Algorithms for Random Walks in the Nonnegative Quarter Plane
Vassilis Kalantzis, Mark S. Squillante, Shashanka Ubaru, Lior Horesh
Workshop on Mathematical performance Modeling and Analysis (MAMA 2022)

PCENet: High Dimensional Surrogate Modeling for Learning Uncertainty
Paz Fink, Shashanka Ubaru, Vassilis Kalantzis, Lior Horesh, Haim Avron
Technical Report, 2022

parGeMSLR: A Parallel Multilevel Schur Complement Low-Rank Preconditioning and Solution Package for General Sparse Matrices
Tianshi Xu, Vassilis Kalantzis, Ruipeng Li, Yuanzhe Xi, Geoffrey Dillon, Yousef Saad
Parallel Computing (To Appear), 2022

Revolutionalizing Numerical Computation with Analog Devices
Vassilis Kalantzis et al.
Technical Report, 2022

Directed Graph Auto-Encoders
Georgios Kollias, Vassilis Kalantzis, Tsuyoshi Ide, Aurelie Lozano, Naoki Abe
In Proceedings of the Thirty-Sixth AAAI Conference on Artificial Intelligence (AAAI 2022)

Enhanced Algebraic Substructuring for Symmetric Generalized Eigenvalue Problems
Vassilis Kalantzis, Lior Horesh
Numerical linear Algebra with Applications (To Appear), 2022


Solving Sparse Linear Systems with Approximate Inverse Preconditioners on Analog Devices
Vassilis Kalantzis, Anshul Gupta, Lior Horesh, Thomas Nowicki, M. S. Squillante, Chai W. Wu, Tayfun Gokmen, Haim Avron
In Proceedings of the 2021 IEEE High Performance Extreme Computing Conference (HPEC 2021)

Fast Randomized non-Hermitian Eigensolvers Based on Rational Filtering and Matrix Partitioning
Vassilis Kalantzis, Yuanzhe Xi, Lior Horesh
SIAM Journal on Scientific Computing 43(5), S791-S815, 2021

Projection Techniques to Update the Truncated SVD of Evolving Matrices with Applications
Vassilis Kalantzis, Georgios Kollias, Shashanka Ubaru, Athanasios N. Nikolakopoulos, Lior Horesh, Kenneth L. Clarkson
In Proceedings of the 2021 International Conference on Machine Learning (ICML 2021)

Sparse Graph Based Sketching for Numerical Linear Algebra
Dong Hu, Shashanka Ubaru, Alex Gittens, Lior Horesh, Kenneth L. Clarkson, Vassilis Kalantzis
In Proceedings of the 2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP 2021)



Stable Computation of Generalized Matrix Functions via Polynomial Interpolation
Jared L. Aurentz, Anthony P. Austin, Michele Benzi, Vassilis Kalantzis
SIAM Journal on Matrix Analysis and Applications 40(1), pp. 210-234, 2019

TeraPCA: a Fast and Scalable Method to Study Genetic Variation in Tera-scale Genotypes
Aritra Bose, Vassilis Kalantzis, Eugenia M. Kontopoulou, Mai Elkadi, Peristera Paschou, Petros Drineas
Bioinformatics 35(19), pp. 3679-3683, 2019


EigenRec: generalizing PureSVD for effective and efficient top-N recommendations
Athanasios N. Nikolakopoulos, Vassilis Kalantzis, Efstratios Gallopoulos, John D. Garofalakis
Knowledge and Information Systems 58(1), pp. 59-81, 2018

Domain decomposition approaches for accelerating contour integration eigenvalue solvers for symmetric eigenvalue problems
Vassilis Kalantzis, James Kestyn, Eric Polizzi, Yousef Saad
Numerical Linear Algebra with Applications 25(5), 2018

A scalable iterative dense linear system solver for multiple right-hand sides in data analytics
Vassilis Kalantzis, A. Cristiano I. Malossi, Costas Bekas, Alessandro Curioni, Efstratios Gallopoulos, Yousef Saad
Parallel Computing 74, pp. 136-153, 2018

A Hierarchical Low Rank Schur Complement Preconditioner for Indefinite Linear Systems
Geoffrey Dillon, Vassilis Kalantzis, Yuanzhe Xi, Yousef Saad
SIAM Journal on Scientific Computing 40(4), A2234-A2252, 2018

Beyond Automated Multilevel Substructuring: Domain Decomposition with Rational Filtering
Vassilis Kalantzis, Yuanzhe Xi, Yousef Saad
SIAM Journal on Scientific Computing 40(4), C477-C502, 2018


Cucheb: A GPU implementation of the filtered Lanczos procedure
Jared L. Aurentz, Vassilis Kalantzis, Yousef Saad
Computer Physics Communications 220, pp. 332-340, 2017

Factored proximity models for top-n recommendations
Athanasios N Nikolakopoulos, Vassilis Kalantzis, Efstratios Gallopoulos, John D Garofalakis
Big Knowledge (ICBK), 2017 IEEE International Conference on, pp. 80--87


Estimating the trace of the matrix inverse by interpolating from the diagonal of an approximate inverse
Lingfei Wu, Jesse Laeuchli, Vassilis Kalantzis, Andreas Stathopoulos, Efstratios Gallopoulos
Journal of Computational Physics 326, pp. 828-844, 2016

Spectral Schur complement techniques for symmetric eigenvalue problems
Vassilis Kalantzis, Ruipeng Li, Yousef Saad
Electronic Transactions on Numerical Analysis 45, pp. 305-329, 2016

PFEAST: A High Performance Sparse Eigenvalue Solver Using Distributed-memory Linear Solvers
James Kestyn, Vassilis Kalantzis, Eric Polizzi, Yousef Saad
In Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis, pp. 16:1--16:12, IEEE Press, 2016


Accelerating data uncertainty quantification by solving linear systems with multiple right-hand sides
Vassilis Kalantzis, Costas Bekas, Alessandro Curioni, Efstratios Gallopoulos
Numerical Algorithms 62(4), pp. 637-653, 2013