-- Version 1 of the paper was entitled "Nearly Optimal Learning and Sparse Covers for Sums of Independent Integer Random Variables" and was published on arxiv on May 4, 2015. ------------------- Version 2 Changes: ------------------- -- Changed the title, revised abstract and intro. -- Added new Fourier-based algorithm that has optimal sample complexity (up to a constant), improving on the algorithm from Version 1 by logarithmic factors. -- Added sample complexity lower bound for any value of k. Version 1 had an optimal sample lower bound for k=2. A generalization of the k=2 approach gives an optimal lower bound for all values of k. -- Added argument that the succinct description of the hypothesis, via its DFT, is efficiently samplable. -- Added simple generic algorithm that applies for any distribution with a sparse FT.