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Title:Local Search Guarantees on Facility Location Problems

Abstract: We will show that guarantees can be given on algorithms for the k-median problem based on local search heuristics.

Title: Vertex Minors

Abstract:

I will give an introduction to vertex-minors of graphs. At first sight vertex minors are a bit peculiar but they are closely related to graph minors and possibly even easier to work with.

Title: Approximating k-Median via Pseudo-Approximation

Abstract: In the last two talks we saw two approaches for approximating k-median.

Title: Razborov's flag algebras: Ten years on

Abstract:

Many of the classical results in extremal combinatorics were obtained by ingenious application of elementary techniques, such as induction and Cauchy-Schwarz inequality.

Title: Hamiltonian Descent Methods

Abstract: In this talk, I will present a paper on the Hamiltonian descent methods

Title:  2-universality of random graphs.

Abstract: For a family of graphs F, a graph G is F-universal if G contains every graph in F as a (not necessarily induced) subgraph.

Title: Approximate Clustering without the Approximation

Abstract: Previously in this CombOpt Reading Group series, we have discussed improving approximation factors for particular distance-based objective functions in clustering problems.

Title: Approximation Algorithms for Distributionally Robust Stochastic Optimization

Abstract:

Two-stage stochastic optimization is a widely-used framework for modeling uncertainty, where we have a probability distribution over possible realizations of the data, called scenarios, and decisions are taken in two stages: we make first-stage decisions knowing only the underlying distribution and before a scenario is realized, and may take additional second-stage recourse actions after a scenario is realized.

Title: Why Random Reshuffling Beats Stochastic Gradient Descent

Abstract:  Over the first few lectures in the seminar we studied the Stochastic Gradient Descent (SGD) method

Title:  A Short Proof of the Containers Theorem for Hypergraphs

Abstract:  A modern trend in extremal combinatorics is extending classical results from the dense setting (e.g. Szemerédi's theorem)