Title: Near-Optimal Column-Based Matrix Reconstruction Speaker: Christos Boutsidis (IBM T. J. Watson Research Center) We consider low-rank reconstruction of a matrix using its columns and we present asymptotically optimal algorithms for both spectral norm and Frobenius norm reconstruction. The main tools we introduce to obtain our results are: (i) the use of fast approximate SVD-like decompositions for column reconstruction, and (ii) two deter ministic algorithms for selecting rows from matrices with orthonormal columns, building upon the sparse representation theorem for decompositions of the identity that appeared in [BSS09]. This is joint work with Petros Drineas and Malik Magdon-Ismail