Saray Shai's Research

Saray Shai

Assistant Professor of Computer Science

Department of Mathematics and Computer Science

Wesleyan University

Email: sshai [at] wesleyan.edu
Office: Exley Science Cetner 643
Address: Department of Mathematics and Computer Science
265 Church St., Science Tower 655 Middletown, CT 06549-0128

Hi, welcome to my webpage! I am an assistant professor in the Mathematics and Computer Science Department at Wesleyan University. My research interests lie in the cross-disciplinary field of Network Science, which aims at analyzing complex systems, such as human cells in the body and individuals in our society, by describing which components interact with one another. My goal is to develop mathematical and computational tools and apply them to data analysis problems arising in a variety of contexts.

I did my undergrad in Mathematics and Computer Science at the Israel Institute of Technology (Technion) and then worked in an Israeli startup called Diligent (which is now part of IBM) offering data "de-duplication" technology (basically, a smart way to identity repeated blocks of data in a huge storage system). Looking for a new challenge, I went back to university to do a PhD in Computer Science. I completed my PhD at the University of St Andrews under the supervision of Simon Dobson. Simon and I discovered our passion for networks together, and it is now a main part of the research of both of us. I did a postdoc in the Mathematics Department at the University of North Carolina at Chapel Hill with Peter J. Mucha.

Research Interests

1. Data analysis and visualization using networks

A main part of my research focuses on the analysis of complex network data like arising in the social, biological and physical sciences. I believe that looking at data through a “network lens” provides us with useful perspectives on diverse problems, and I am constantly looking for new datasets on which I can apply my “network machinery” to solve real-world problems and to inspire the development of new methodologies.

- Network science applications in cancer care research: we analyzed care-coordination networks between physicians in multi-specialty teams that provided care to patients diagnosed with colorectal cancer, and compared networks obtained through different payers (private vs public).
- Network science applications in urban planning and engineering: check out our recent work on the analysis of the coupling between the street network and the subway in the two large metropolitan areas of London and New York City. I am currently developing another urban congestions model based on tools from Riemannian geometry.

2. Analytical and computational frameworks for modeling complex systems

One of the ultimate goals of network science is to understand the implications of emerging non-trivial structures to the behavior and functionality of networked dynamical systems, and how these in turn affect the structural evolution of the network. This was the main line of research that I pursued during my graduate work in Computer Science and is still an active direction that I am very interested in.

- Epidemic spreading in adaptive networks: I developed an analytical framework (based on numerical analysis of nonlinear ODEs) supported by numerical simulation (which is a C++ implementation of the Gillespie algorithm) to study SIS model in adaptive networks.

3. Network robustness using percolation theory

I am interested in "realistic percolation models" to study the response of networks (e.g. critical infrastructures) to failures and attacks.

Percolation of modular and interdependent networks: we developed the analytical framework to study the resilience of modular organization of interconnected and interdependent systems showing that interdependent infrastructures can be susceptible to failure or attacks causing the system to break into separate modules. We have recently discovered that percolation of modular networks can be described using the mathematics of magnetism under external field.

4. Community (cluster) detection and other structures

Community structure is thought to be one of the main organizing principles in most complex networks. A quantitative description of the grouping patterns of entities in a system, such as social communities, is often very hard to find and requires powerful mathematical tools and large-scale data manipulation techniques.

Inferring stochastic block models in multilayer networks: check out our new generative model for community structure in multilayer networks demonstrated microbial interaction networks extracted from the Human Microbiome Project.
Detectability of community structure in multilayer networks: check out our new theory based on random matrices (RMT) to find a phase transition in the detectability of structures in multilayer network.

5. Multilayer networks

Multilayer networks is a mathematical framework that incorporates "multilayer features" (e.g. multiple subsystems and layers of connectivity) into traditional network theory. I am interesting in extending exiting network methods to support time-dependence among interactions, consider interactions among arbitrary numbers of entities, and multiple modes of interactions that take place simultaneously. I would like to better understand the challenges that practitioners face when coming to analyze different types of time-varying, multi-relational and multi-scale datasets.

What's been going on

March 2022: Giving a lecture at the pre-conference school at the Fifth Northeast Regional Conference on Complex Systems (NERCCS 2022) in SUNY Buffalo, NY.
March 2022: Giving a lecture at a local school (grades 4-6) to celebrate International Women's Day.
January 2021: Going on sabbatical in Israel!
October 2021: Our paper "One Node at a Time: Node-Level Network Classification" was accepted to ICMLA 2021
July 2021: Our paper "A guide to choosing and implementing reference models for social network analysis" was accepted to Biological Reviews.
Giving an REU seminar at the Center for Discrete Mathematics & Theoretical Computer Science (DIMACS) at Rutgers University, NJ.
February 2021: Our paper "Geographic impressions in Facebook political ads" was accepted to Applied Network Science.
November 2020: Giving a talk at the Galilee Research Center for Applied Mathematics at ORT Braude College, Israel.
September 2020: Attending the Grace Hopper Celebration for the first time!
June 2020: My first NSF grant was funded.
Apr 2020: Giving a talk at the Third Northeast Regional Conference on Complex Systems (NERCCS 2020) in SUNY Buffalo, NY.
Oct 2019: Working group at the National Institute for Mathematical and Biological Synthesis (NIMBioS) on "Null models in social behavior".
August 2019: Teaching two modules (on binary numbers and search algorithms) at the Girls in Science Summer Camp at Wesleyan.
April 2019: Co-organized (together with Random Hacks of Kindness Jr., and the Patricelli Center) "Youth coding for a cause hackathon” where participants from local schools (grade 4 through 8) are working with Wesleyan student mentors to create technology for social good.
Apr 2019: Our paper on Comparing Shared Patient Networks Across Payers was accepted to the Journal of General Internal Medicine.
Nov 2018: Giving a talk at the Center for Collective Dynamics of Complex Systems at Binghamton University.
Jul 2018: Our paper on the resilience of networks with community structure behaves as if under an external field was accepted to PNAS.
May 2018: Our paper on Care Coordination and Multispecialty Teams in the Care of Colorectal Cancer Patients was accepted to Medical care.
Oct 2017: Our paper on the scaling structure of the global road networks was accepted to The Royal Society Interface.
Jun 2017: New paper on the arXiv: Case studies in network community detection.
May 2017: New paper on the arXiv: The scaling structure of the global road network.
Jan 2017: Giving a talk at NetSciX 2017 in Hilton Tel Aviv, Israel.
Nov 2016: Participating in the Mathematics Academic Job Search Panel in our department.
Jul 2016: I joined the editorial board of Nature Scientific Data, a peer-reviewed, open-access journal for descriptions of research datasets.
Jul 2016: Presenting a poster at the SIAM Workshop on Network Science (NS16) in Boston, MA.
Jun 2016: Participating in the Girls Talk Math Camp aiming to encourage girls to consider careers in mathematics!
Jun 2016: Attending the Italy-Israel meeting "Simplifying Complex Biological Systems" In Memory of Prof. Eshel Ben-Jacob in Tel Aviv, Israel.
May 2016: Our paper on detectability of community structure in multilayer networks was accepted to Physical Review Letters.
Mar 2016: Giving a talk at the workshop on Generalized Network Structures and Dynamics in the Mathematical Biosciences Institute (MBI), OH.
Feb 2016: Our paper on stochastic block models in multilayer networks has been accepted to IEEE Transactions on Network Science and Engineering.
Jan 2016: Presenting a poster at Dynamics Days in Durham, NC.
Dec 2015: Giving a talk at the Network Frontier Workshop at Northwestern University in Evanston, IL.
Nov 2015: New paper on the arXiv: Enhanced detectability of community structure in multilayer networks through layer aggregation.
Nov 2015: Our figure is featured on the cover of this Issue of the Royal Society Interface!
Sep 2015: Our recent work on multilayer transportation networks was mentioned in the New Scientist, the BBC and the Wired!
Sep 2015: Our paper on multiplex networks was accepted to the Royal Society Interface.
Aug 2015: New paper on the arXiv: Multiplex networks in metropolitan areas: generic features and local effects.
Aug 2015: New paper on the arXiv: Resilience of Networks Formed of Interdependent Modular Networks.
Jul 2015: Giving a talk at the workshop Mathematics and Physics of Multilayer Networks at the Max Planck Institute for the Physics of Complex Systems in Dresden, Germany.
Jul 2015: New paper on the arXiv: Clustering network layers with the strata multilayer stochastic block model.
Jun 2015: Presenting a poster at NetSci 2015 in Zaragoza, Spain.
Jun 2015: Giving a a talk at the satellite symposium Networks of Networks for NetSci 2015 in Zaragoza, Spain.
Jun 2015: Giving a a talk at the satellite symposium Information, Self-Organizing Dynamics and Synchronization on Complex Networks II (ISODSII) for NetSci 2015 in Zaragoza, Spain.
May 2015: Organizing a minisymposium with Nishant Malik "Complex Network Theory Based Approaches in the Analyses of Complex Systems and Data" at the SIAM Conference on Applications of Dynamical Systems in Snowbird, UT.
Mar 2015: Attending the 6th Workshop on Complex Networks (CompleNet 2015) in New York City, NY.
Mar 2015: Giving a talk at Duke Network Analysis Center (DNAC) in Durham, NC.
Dec 2014: Presenting a poster at the Advances in Discrete Networks Workshop in Pittsburgh, PA.
Jul 2014: Giving a talk at the SIAM Workshop on Network Science (NS14) in Chicago, IL.
Nov 2013: Giving a talk at Stirling PG Tips in Stirling, Scotland.
Nov 2013: Attending the SICSA DEMOFest in Glasgow, Scotland.
Aug 2013: Attending St Andrews Computer Science PhD Reading Party in The Burn, Scotland.
Jul 2013: Participating in the Lipari Summer School on Computational Complex Systems in Lipari Island, Italy.
Jun 2013: Presenting a poster at the Workshop on Dynamics of Biological Networks in Edinburgh, Scotland.
Jun 2013: Presenting a poster at the SICSA PhD Conference in Stirling, Scotland.
Jun 2013: Presenting a poster at the International Conference on Network Science (NetSci 2013) in Copenhagen, Denmark.
May 2013: Attending a SICSA workshop on Cyber-Physical Systems in Edinburgh, Scotland.
May 2013: Attending the Women in Computing Panel in Edinburgh, Scotland.
Mar 2013: Giving a talk at the Centre for GeoInformatics Seminar Series in St Andrews, Scotland.
Jan 2013: Giving a talk at the System Seminar Series in my department in St Andrews, Scotland.
Nov 2012: Giving a talk at the SICSA Prize Studentship Induction Day in Edinburgh, Scotland.
Sep 2012: Giving a talk at the joint workshop on Compositional Modeling and Analysis of Quantitative Systems (MLQA 2012) in Edinburgh, Scotland.
Jun 2012: Presenting a poster at SICSA PhD Conference in Glasgow, Scotland.
May 2012: Giving a talk at ”Biology + Computing = ??” in Stirling, Scotland.
May 2012: Attending the Women in Computing Panel in Edinburgh, Scotland.
Mar 2012: Giving a talk at the SICSA International Advisory Board meeting in Glasgow, Scotland.
Oct 2011: Attending the Second SICSA Workshop on Biological Networks in Edinburgh, Scotland.
Aug 2011: Attending SICSA Workshop on Critical Infrastructure Interdependencies in Glasgow, Scotland.
May 2011: Presenting a poster at the SICSA PhD Conference in Edinburgh, Scotland. Won the best poster award!

Page updated

Google Sites

Report abuse