Over the past two decades, recommender systems have become ubiquitous -- we use recommendation technology whenever we shop at Amazon, watch movies on Netflix or browse any social networking website. We analyze the history, current trends, threats and the future potential of recommender...

We present a systematic investigation of { [[EQUATION]] } extension twinning mechanism in single crystal magnesium micropillars deformed over seven orders of magnitude of strain rate, from 10-4 to 500 s-1, revealing how the accommodation of newly formed twins evolves with and depends on the...

We derive general, yet simple, sharp bounds on the size of the omitted variable bias for a broad class of causal parameters that can be identified as linear functionals of the conditional expectation function of the outcome. Such functionals encompass many of the traditional targets of...