Energy inequalities for cutoff functions and some applications

We consider a metric measure space with a local regular Dirichlet form. We establish necessary and sufficient conditions for upper heat kernel bounds with sub-diffusive space-time exponent to hold. This characterization is stable under rough isometries, that is it is preserved under bounded perturbations of the Dirichlet form. Further, we give a criterion for stochastic completeness in terms of a Sobolev inequality for cutoff functions. As an example we show that this criterion applies to an anomalous diffusion on a geodesically incomplete fractal space, where the well-established criterion in terms of volume growth fails

Optimal taxation in infinitely-lived agent and overlapping generations models : a review

Fiscal policy ; Taxation

Heat kernel estimates and intrinsic metric for random walks with general speed measure under degenerate conductances

We establish heat kernel upper bounds for a continuous-time random walk under unbounded conductances satisfying an integrability assumption, where we correct and extend recent results by the authors to a general class of speed measures. The resulting heat kernel estimates are governed by the intrinsic metric induced by the speed measure. We also provide a comparison result of this metric with the usual graph distance, which is optimal in the context of the random conductance model with ergodic conductances.Comment: 19 pages; accepted version, to appear in Electron. Commun. Proba

Quality of Life in Buenos Aires Neighborhoods: Hedonic Price Regressions and the Life Satisfaction Approach

This paper studies quality of life in urban neighborhoods in the Buenos Aires Metropolitan Area. First, hedonic price regressions for residential prices are augmented with neighborhood characteristics, based on a real estate database with indicators on each property’s distance to public facilities and amenities, and on a smaller survey with greater detail. Second, following recent developments in the field of happiness research, the document assesses the importance of different neighborhood characteristics on quality of life by interacting objective and subjective indicators. Indices of quality of life related to local amenities are derived for the different neighborhoods for both the hedonic regression and life satisfaction approaches. The results indicate a strong but not perfect correlation between real estate prices, income levels and neighborhood characteristics, suggesting scope for welfare-improving policy interventions.

Simple root flows for Hitchin representations

We study simple root flows and Liouville currents for Hitchin representations. We show that the Liouville current is associated to the measure of maximal entropy for a simple root flow, derive a Liouville volume rigidity result, and construct a Liouville pressure metric on the Hitchin component.Comment: Dedicated to Bill Goldman on the occasion of his 60th birthda

Preliminary results in tag disambiguation using DBpedia

The availability of tag-based user-generated content for a variety of Web resources (music, photos, videos, text, etc.) has largely increased in the last years. Users can assign tags freely and then use them to share and retrieve information. However, tag-based sharing and retrieval is not optimal due to the fact that tags are plain text labels without an explicit or formal meaning, and hence polysemy and synonymy should be dealt with appropriately. To ameliorate these problems, we propose a context-based tag disambiguation algorithm that selects the meaning of a tag among a set of candidate DBpedia entries, using a common information retrieval similarity measure. The most similar DBpedia en-try is selected as the one representing the meaning of the tag. We describe and analyze some preliminary results, and discuss about current challenges in this area

Quenched invariance principle for random walks with time-dependent ergodic degenerate weights

We study a continuous-time random walk, $X$, on $\mathbb{Z}^d$ in an environment of dynamic random conductances taking values in $(0, \infty)$. We assume that the law of the conductances is ergodic with respect to space-time shifts. We prove a quenched invariance principle for the Markov process $X$ under some moment conditions on the environment. The key result on the sublinearity of the corrector is obtained by Moser's iteration scheme.Comment: 34 pages; in this version a minor technical gap in the proof of the results in Section 5 has been remove