Skyline Identification in Multi-Armed Bandits

We introduce a variant of the classical PAC multi-armed bandit problem. There is an ordered set of $n$ arms $A[1],\dots,A[n]$, each with some stochastic reward drawn from some unknown bounded distribution. The goal is to identify the $skyline$ of the set $A$, consisting of all arms $A[i]$ such that $A[i]$ has larger expected reward than all lower-numbered arms $A[1],\dots,A[i-1]$. We define a natural notion of an $\varepsilon$-approximate skyline and prove matching upper and lower bounds for identifying an $\varepsilon$-skyline. Specifically, we show that in order to identify an $\varepsilon$-skyline from among $n$ arms with probability $1-\delta$, $$\Theta\bigg(\frac{n}{\varepsilon^2} \cdot \min\bigg\{ \log\bigg(\frac{1}{\varepsilon \delta}\bigg), \log\bigg(\frac{n}{\delta}\bigg) \bigg\} \bigg)$$ samples are necessary and sufficient. When $\varepsilon \gg 1/n$, our results improve over the naive algorithm, which draws enough samples to approximate the expected reward of every arm; the algorithm of (Auer et al., AISTATS'16) for Pareto-optimal arm identification is likewise superseded. Our results show that the sample complexity of the skyline problem lies strictly in between that of best arm identification (Even-Dar et al., COLT'02) and that of approximating the expected reward of every arm.Comment: 18 pages, 2 Figures; an ALT'18/ISIT'18 submissio

Letter to Father

Produced by The Center on Disability Studies, University of Hawai'i at Manoa, Honolulu, Hawai'i and The School of Social Sciences, The University of Texas at Dallas, Richardson, Texas for The Society for Disability Studies

Análisis de alternativa para el transporte internacional de productos de cuidado personal de Colombia hacia argentina

El presente artículo se estructura dada la necesidad de Belcorp para encontrar una alternativa intermedia de transporte para el abastecimiento de sus productos de cuidado personal desde Colombia hacia Argentina, esto debido a las dificultades logísticas que se están presentando en la ruta actual marítima que han ocasionado que los tiempos de tránsito no sean estables para la definición de un tiempo de abastecimiento estándar. El determinar un tiempo más ajustado podría contribuir a suplir eficientemente las necesidades de consumo de estos productos para el mercado del país. De esta forma dentro de un análisis logístico realizado por el área de Comercio Exterior, se plantearon a las áreas interesadas tres opciones de transporte donde se analizaron costos, tiempos, aspectos aduaneros y de comercio internacional hallando la mejor opción, sobre la cual se realizó una prueba piloto para confirmar la concordancia de los datos obtenidos en la investigación inicial. Aunque en esta prueba piloto no se logró cumplir con los tiempos y costos planeados, se identificaron acciones de mejora alcanzables y cumplibles que con su desarrollo se podría considerar la implementación de la ruta como la opción alternativa que se desea encontrar.This article is structured because the necessity of Belcorp to find for an intermediate transportation alternative to supply their personal care products from Colombia to Argentina, this is due to the logistical difficulties that are occurring in the current path by sea that have caused unstable transit times for the definition of a standard Lead time. Determining an adjusted transit time could help to meet the needs of demand of these products efficiently to the market of Argentina. Thus, within a logistic analysis conducted by the Foreign Trade area, were raised to the areas concerned four options which analyzed transportation costs, time, aspects of customs formalities and international trade, and finding the best option on which was performed a pilot to confirm the consistency of the data obtained in the initial research. Although this pilot was not able to meet the planned time and cost, accomplishable and achievable improvement actions were identified and its development could consider implementing the route as the alternative option to be found

A Preliminary Look at the Physics Reach of a Solar Neutrino TPC: Time-Independent Two Neutrino Oscillations

This paper will discuss the physics reach of a solar neutrino TPC containing many tons of He4 under high pressure. Particular attention is given to the LMA and SMA solutions, which are allowed by current data, and which are characterized by a lack of time-dependent phenomena (either summer-winter or day-night asymmetries). In this case, the physics of neutrino masses and mixing is all contained in the energy dependence of the electron neutrino survival probability, (or in its reciprocal, the electron neutrino disappearance probability).Comment: 19 pages, 12 figure

Association of Systemic Inflammation With Retinal Vascular Caliber in Patients With AIDS.

PurposeTo evaluate relationships among retinal vascular caliber and biomarkers of systemic inflammation in patients with AIDS.MethodsA total of 454 participants with AIDS had retinal vascular caliber (central retinal artery equivalent and central retinal vein equivalent) determined from enrollment retinal photographs by reading center graders masked to clinical and biomarker information. Cryopreserved plasma specimens were assayed for inflammatory biomarkers, including C-reactive protein (CRP), IL-6, interferon-γ inducible protein (IP)-10, kynurenine/tryptophan (KT) ratio, and intestinal fatty acid binding protein (I-FABP).ResultsIn the simple linear regression of retinal vascular caliber on plasma biomarkers, elevated CRP, IL-6, and IP-10 were associated with retinal venular dilation, and elevated KT ratio with retinal arteriolar narrowing. In the multiple linear regression, including baseline characteristics and plasma biomarkers, AMD was associated with dilation of retinal arterioles (mean difference: 9.1 μm; 95% confidence interval [CI] 5.2, 12.9; P < 0.001) and venules (mean difference, 10.9 μm; 95% CI, 5.3, 16.6; P < 0.001), as was black race (P < 0.001). Hyperlipidemia was associated with retinal venular narrowing (mean difference, -7.5 μm; 95% CI, -13.7, -1.2; P = 0.02); cardiovascular disease with arteriolar narrowing (mean difference, -5.2 μm; 95% CI, -10.3, -0.1; P = 0.05); age with arteriolar narrowing (slope, -0.26 μm/year; 95% CI, -0.46, -0.06; P = 0.009); and IL-6 with venular dilation (slope, 5.3 μm/standard deviation log10[plasma IL-6 concentration]; 95% CI, 2.7, 8.0; P < 0.001).ConclusionsThese data suggest that retinal vascular caliber is associated with age, race, AMD, hyperlipidemia, cardiovascular disease, and selected biomarkers of systemic inflammation

Theory and applications of supercycled symmetry-based recoupling sequences in solid-state NMR

We present the theoretical principles of supercycled symmetry-based recoupling sequences in solid-state magic-angle-spinning NMR. We discuss the construction procedure of the SR26 pulse sequence, which is a particularly robust sequence for double-quantum homonuclear dipole-dipole recoupling. The supercycle removes destructive higher-order average Hamiltonian terms and renders the sequence robust over long time intervals. We demonstrate applications of the SR26 sequence to double-quantum spectroscopy, homonuclear spin counting, and determination of the relative orientations of chemical shift anisotropy tensors