| Monday 22 July 2024 | |
| Events for day: Wednesday 29 May 2024 |
| 14:00 - 15:00 Combinatorics and Computing Weekly Seminar Hierarchical clustering via local search School MATHEMATICS In this talk I first give a short introduction to hierarchical clustering. Then I introduce Dasgupta's unsupervised objective function for hierarchical clustering (STOC 2016) and its dual version as studied by Moseley and Wang (NIPS 2017). Then I introduce a local search framework for hierarchical clustering and present some analysis of the locally optimal solutions within this framework based on Moseley and Wang revenue function. Furthermore a connection with the popular average linkage algorithm is established. If time allows, I show an implementation of the local search algorithm with some empirical results. Zoom room informat ... 17:30 - 19:00 Algebraic Geometry Biweekly Webinar Linear Combinations of Cohomological Invariants of Compact Complex Manifolds School MATHEMATICS In the 50s, Hirzebruch asked which linear combinations of Hodge and Chern numbers are topological invariants of compact complex manifolds. Building on ideas of Schreieder and Kotschick, who solved the K�hler case, I will present a general answer to this question (and some related ones). Furthermore, I will outline a program how to tackle similar questions when incorporating more cohomological invariants, eg the dimensions of the Bott Chern cohomology groups. This will naturally lead to an algebraic study of the structure of bicomplexes, as well as a number of challenging geometric construction problems. https://zoom.us/j ... |