Invariant multidimensional matrices

A rank $n$ Steiner bundle on $\P^n$ which is SL(2,\C) invariant is a Schwarzenberger bundleComment: preuve simplifiee d'un resultat d'Ancona et Ottavian

Coupled ethical-epistemic analysis of public health research and practice: categorizing variables to improve population health and equity

The categorization of variables can stigmatize populations, which is ethically problematic and threatens the central purpose of public health: to improve population health and reduce health inequities. How social variables (e.g., behavioral risks for HIV) are categorized can reinforce stigma and cause unintended harms to the populations practitioners and researchers strive to serve.<p></p> Although debates about the validity or ethical consequences of epidemiological variables are familiar for specific variables (e.g., ethnicity), these issues apply more widely.<p></p> We argue that these tensions and debates regarding epidemiological variables should be analyzed simultaneously as ethical and epistemic challenges. We describe a framework derived from the philosophy of science that may be usefully applied to public health, and we illustrate its application.<p></p&gt

Cooper pair islanding model of insulating nanohoneycomb films

We first review evidence for the Cooper pair insulator (CPI) phase in amorphous nanohoneycomb (NHC) films. We then extend our analysis of superconducting islands induced by film thickness variations in NHC films to examine the evolution of island sizes through the magnetic field-driven SIT. Finally, using the islanding picture, we present a plausible model for the appearance and behavior of the CPI phase in amorphous NHC films

Appraising fiscal reaction functions

We estimate fiscal responses for an OECD panel, accounting for cross-country interactions, and also estimate the fiscal responses in a panel VAR. We find that governments have increased primary balances when facing higher government indebtedness, implying a Ricardian fiscal regime, while primary balances have improved to reduce government debt. These results hold for the single regression panel analysis and for the panel VAR.fiscal regimes, Panel VAR, cross-sectional dependence Classification-C23, E62, H62

Measuring the Success of Fiscal Consolidations

We measure the success of fiscal consolidation, with alternative definitions, based on ad-hoc quantitative approaches and on a policy-action approach. The cyclically adjusted primary balance, and the duration of the consolidation contribute for its success, and the opposite applies for revenue based consolidations.fiscal episodes, panel data, logit Classification-C23, E62, H50, H62

Consistent Sensor, Relay, and Link Selection in Wireless Sensor Networks

In wireless sensor networks, where energy is scarce, it is inefficient to have all nodes active because they consume a non-negligible amount of battery. In this paper we consider the problem of jointly selecting sensors, relays and links in a wireless sensor network where the active sensors need to communicate their measurements to one or multiple access points. Information messages are routed stochastically in order to capture the inherent reliability of the broadcast links via multiple hops, where the nodes may be acting as sensors or as relays. We aim at finding optimal sparse solutions where both, the consistency between the selected subset of sensors, relays and links, and the graph connectivity in the selected subnetwork are guaranteed. Furthermore, active nodes should ensure a network performance in a parameter estimation scenario. Two problems are studied: sensor and link selection; and sensor, relay and link selection. To solve such problems, we present tractable optimization formulations and propose two algorithms that satisfy the previous network requirements. We also explore an extension scenario: only link selection. Simulation results show the performance of the algorithms and illustrate how they provide a sparse solution, which not only saves energy but also guarantees the network requirements.Comment: 27 pages, 17 figure