SQUIDS Seminar: Sean Holman

About

Speaker: Sean Holman (University of Manchester) Title: Confidence intervals for Landweber reconstruction using randomised normal operator approximation Abstract: We analyse the propagation of error through the Landweber iteration, establishing confidence regions with statistical coverage guarantees. For large problems, calculation of the confidence regions is prohibitively expense, and to make this feasible we introduce randomised approximation of the normal operator. This approximation also adds a second layer of regularisation, which avoids excessively large confidence regions. We are motivated by X-ray CT and provide some numerical experiments, calculating reconstructions with confidence intervals, in that context. This is based on joint work with Anuj Abhishek.