My research program is to use combinatorial structures for mathematical modeling and algorithm design in the context of massive data and social network analyses.   

In this context, I study mixing times of Markov chains, I develop new statistical tools in non-i.i.d. regimes or the usages of the Markov chain Monte Carlo method, I design algorithms in various graph mining models, I use partially ordered sets or permutations when data has a hierarchical structure, and I introduce mathematical measures to analyze social issues in online networks. 


Selected Publications: 

Please find my full list of publications on Google scholar or dblp.


Optimally Improving Cooperative Learning in a Social Setting                                                                                             PDF

(ICML 2024)

S Haddadan, C Xin, J Gao


DeMEtRIS: Counting (near)-Cliques by Crawling                                                                                                                         PDF

(WSDM 2023)  Ranked among top 10 papers and invited to the special issue of the ACM Transactions on Intelligent Systems

SK Bera, J Choudhari, S Haddadan, S Ahmadian

Reducing polarization and increasing diverse navigability in graphs by inserting edges and swapping edge weights

(ACM transactions on Data Mining and Knowledge Discovery 2022)                                                                                                           PDF 

S Haddadan, C Menghini, M Riondato, E Upfal 


Fast Doubly-Adaptive MCMC to Estimate the Gibbs Partition Function with Weak Mixing Time Bounds            PDF

(NeurIPS 2021)

S Haddadan, Y Zhuang, C Cousins, E Upfal 


Repbublik: Reducing polarized bubble radius with link insertions                                                                              PDF

(WSDM 2021  Best paper honorable mention 

S Haddadan, C Menghini, M Riondato, E Upfal


Some Instances of Homomesy Among Ideals of Posets                                                                                                PDF

(The Electronic Journal of Combinatorics 2021)

S Haddadan


Mallows models for top-k lists                                                                                                                                            PDF

(NeurIPS 2018)

F Chierichetti, A Dasgupta, S Haddadan, R Kumar, S Lattanzi


On the Complexity of Sampling Vertices Uniformly from a Graph                                                                               PDF

(ICALP 2018)

F Chierichetti, S Haddadan


Mixing of Permutations by Biased Transpositions                                                                                                          PDF

(Theory of Computing Systems TOCS, 2018)

S Haddadan, P Winkler


Mixing of Permutations by Biased Transposition                                                                                                            PDF

(STACS 2017)   Invited to the special issue of Theory of Computing Systems

S Haddadan, P Winkler


The expected jaggedness of order ideals                                                                                                                          PDF

(Forum of Mathematics Sigma, 2017)

M Chan, S Haddadan, S Hopkins, L Moci