{"672804":{"#nid":"672804","#data":{"type":"event","title":"[Postponed] CSE Faculty Candidate Seminar - Robert Webber","body":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003EThis CSE faculty recruiting seminar has been postponed from February 13 due to unforeseen circumstances. We will announce the seminar\u0027s date and location at a later time.\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EName: \u003C\/strong\u003E\u003Cspan\u003E\u003Cspan\u003ERobert Webber, CMX postdoctoral fellow at California Institute of Technology\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDate: \u003C\/strong\u003ETBD\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELocation:\u003C\/strong\u003E\u0026nbsp;TBD\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELink:\u0026nbsp;\u003C\/strong\u003EThe recording of this in-person seminar will be uploaded to\u0026nbsp;\u003Ca href=\u0022https:\/\/mediaspace.gatech.edu\/channel\/School%2Bof%2BComputational%2BScience%2Band%2BEngineering\/259332602\u0022 target=\u0022_blank\u0022\u003ECSE\u0027s MediaSpace\u003C\/a\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ETitle:\u0026nbsp;\u003C\/strong\u003ERandomized Matrix Decompositions for Faster Scientific Computing\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003EAbstract:\u003C\/strong\u003E Traditional numerical methods based on expensive matrix factorizations struggle with the scale of modern scientific applications. For example, kernel-based algorithms take a data set of size N, form the kernel matrix of size N x N, and then perform an eigendecomposition or inversion at a cost of O(N^3) operations. For data sets of size N \u0026gt;= 10^5, kernel learning is too expensive, straining the limits of personal workstations and even dedicated computing clusters. Randomized iterative methods have emerged as a faster alternative to the classical approaches. These methods combine randomized exploration with information about which matrix structures are important, leading to significant speed gains.\u003C\/span\u003E\u003C\/span\u003E\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\n\u003Cspan\u003E\u003Cspan\u003EIn this talk, I will review recent developments concerning two randomized algorithms. The first is \u0022randomized block Krylov iteration\u0022, which uses an array of random Gaussian test vectors to probe a large data matrix in order to provide a randomized principal component analysis. Remarkably, this approach works well even when the matrix of interest is not low-rank. The second algorithm is \u0022randomly pivoted Cholesky decomposition\u0022, which iteratively samples columns from a positive semidefinite matrix using a novelty metric and reconstructs the matrix from the randomly sampled columns. Ultimately, both algorithms furnish a randomized approximation of an N x N matrix with a reduced rank k \u0026lt;\u0026lt; N, which enables fast inversion or singular value decomposition at a cost of O(N k^2) operations. The speed-up factor from N^3 to N k^2 operations can be 3 million. The newest algorithms achieve this speed-up factor while guaranteeing performance across a broad range of input matrices.\u003C\/span\u003E\u003C\/span\u003E\u003Cbr \/\u003E\r\n\u003Cbr \/\u003E\r\n\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003EBio:\u003C\/strong\u003E Robert Webber is currently a CMX postdoctoral fellow in Caltech\u0027s Department of Computing + Mathematical Sciences, hosted by Joel Tropp. Before that, Robert was a Ph.D. student in mathematics at the Courant Institute of Mathematical Sciences, advised by Jonathan Weare. Robert studies randomized numerical methods and their applications to data science and scientific computation.\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003EThis CSE faculty recruiting seminar has been postponed from February 13 due to unforeseen circumstances. We will announce the seminar\u0027s date and location at a later time.\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EName: \u003C\/strong\u003E\u003Cspan\u003E\u003Cspan\u003ERobert Webber, CMX postdoctoral fellow at California Institute of Technology\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003EDate: \u003C\/strong\u003ETBD\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELocation:\u003C\/strong\u003E\u0026nbsp;TBD\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ELink:\u0026nbsp;\u003C\/strong\u003EThe recording of this in-person seminar will be uploaded to\u0026nbsp;\u003Ca href=\u0022https:\/\/mediaspace.gatech.edu\/channel\/School%2Bof%2BComputational%2BScience%2Band%2BEngineering\/259332602\u0022 target=\u0022_blank\u0022\u003ECSE\u0027s MediaSpace\u003C\/a\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cstrong\u003ETitle:\u0026nbsp;\u003C\/strong\u003ERandomized Matrix Decompositions for Faster Scientific Computing\u003C\/p\u003E\r\n","format":"limited_html"}],"field_summary_sentence":[{"value":"Seminar Title:\u00a0Randomized Matrix Decompositions for Faster Scientific Computing"}],"uid":"36319","created_gmt":"2024-02-07 02:38:36","changed_gmt":"2024-02-12 18:29:06","author":"Bryant Wine","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2024-02-13T11:00:00-05:00","event_time_end":"2024-02-13T12:00:00-05:00","event_time_end_last":"2024-02-13T12:00:00-05:00","gmt_time_start":"2024-02-13 16:00:00","gmt_time_end":"2024-02-13 17:00:00","gmt_time_end_last":"2024-02-13 17:00:00","rrule":null,"timezone":"America\/New_York"},"location":"Coda, 9th Floor Atrium","extras":["free_food"],"hg_media":{"672996":{"id":"672996","type":"image","title":"Robert Webber Headshot.jpg","body":null,"created":"1707273561","gmt_created":"2024-02-07 02:39:21","changed":"1707273561","gmt_changed":"2024-02-07 02:39:21","alt":"CSE Robert Webber","file":{"fid":"256336","name":"Robert Webber Headshot.jpg","image_path":"\/sites\/default\/files\/2024\/02\/06\/Robert%20Webber%20Headshot.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/2024\/02\/06\/Robert%20Webber%20Headshot.jpg","mime":"image\/jpeg","size":503073,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/2024\/02\/06\/Robert%20Webber%20Headshot.jpg?itok=oicaNdB1"}}},"media_ids":["672996"],"groups":[{"id":"47223","name":"College of Computing"},{"id":"50877","name":"School of Computational Science and Engineering"}],"categories":[],"keywords":[{"id":"166983","name":"School of Computational Science and Engineering"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"177814","name":"Postdoc"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EMary High\u003Cbr \/\u003E\r\nmhigh7@gatech.edu\u003C\/p\u003E\r\n","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}