Jacob Fox Quantitative Property Testing Abstract: Over the last couple of decades, it has become abundantly clear that the analysis of big data is of great importance, and yet traditional algorithms are too slow to be effective. In recent years, very general results in property testing have been established which give "constant time" algorithms for many natural problems. Here, the running time is independent of the input size, but does depend on a tolerance parameter. The proof of these results utilize regularity methods pioneered by Szemeredi, and give tower-type or worse dependencies on the tolerance parameter, which is useless in practice. It is therefore a fundamental problem to determine whether new proofs can be found which give better bounds. In this talk, I will discuss recent progress on this problem and some closely related major problems in combinatorics and number theory.