This document summarizes Austin Benson's presentation on QR factorizations and SVDs for tall-and-skinny matrices in MapReduce architectures. It discusses how communication-avoiding TSQR and indirect/direct TSQR algorithms can be implemented in MapReduce frameworks to compute QR factorizations and SVDs of large matrices in a distributed, parallel manner. It also compares the performance of different MapReduce algorithms for computing QR on various sized matrices.