Logarithmic Jet Bundles and Applications

We generalize Demailly's construction of projective jet bundles and strictly negatively curved pseudometrics on them to the logarithmic case. We establish this logarithmic generalization explicitly via coordinates, just as Noguchi's generalization of the jets used by Green-Griffiths. As a first application, we give a metric proof for the logarithmic version of Lang's conjecture concerning the hyperbolicity of complements of divisors in a semi-abelian variety as well as for the corresponding big Picard theorem.Comment: 49 pages, Late

Optimal Inference in Crowdsourced Classification via Belief Propagation

Crowdsourcing systems are popular for solving large-scale labelling tasks with low-paid workers. We study the problem of recovering the true labels from the possibly erroneous crowdsourced labels under the popular Dawid-Skene model. To address this inference problem, several algorithms have recently been proposed, but the best known guarantee is still significantly larger than the fundamental limit. We close this gap by introducing a tighter lower bound on the fundamental limit and proving that Belief Propagation (BP) exactly matches this lower bound. The guaranteed optimality of BP is the strongest in the sense that it is information-theoretically impossible for any other algorithm to correctly label a larger fraction of the tasks. Experimental results suggest that BP is close to optimal for all regimes considered and improves upon competing state-of-the-art algorithms.Comment: This article is partially based on preliminary results published in the proceeding of the 33rd International Conference on Machine Learning (ICML 2016

The Super Size of America: An Economic Estimation of Body Mass Index and Obesity in Adults

The increased prevalence of obesity in the US stresses the need for answers as to why this rapid rise has occurred. This paper employs micro-level data from the First, Second, and Third National Health and Nutrition xamination Surveys to determine the effects that state-level policies have on BMI and obesity. These policies, which include restaurants per capita, the gasoline tax, the cigarette tax, and clean indoor air laws, display many of the expected effects on obesity and explain a substantial amount of its trend. We control for individual-level measures of household income, years of formal schooling completed, and marital status.