Cerveza 0,0, refrescos `zeroï y productos light.

Artículo que muestra el uso de las cifras en la publicidad, en algunos casos de forma engañosa. La cerveza sin alcohol, o los refrescos y productos light son algunos de los ejemplos en los que la aritmética juega un papel importante, el cual se expone desde un punto de vista matemático.

Pressupostos 2001 i dèficit zero. 'Presupuestos 2001 y déficit cero'.

El artículo analiza la política presupuestaria del MEC una vez hechas las transferencias y traspasos desde la Administración Central a las diecisiete CCAA en materia de educación. También analiza el presupuesto 2001 del Departament d'Ensenyament. Lo hace comparándolo con el presupuesto total de la Generalitat y con el PIB.

El projecte educatiu de barri en un entorn socioeconòmic desfavorit : des de zero anys fins a l'escola d'adults. 'El proyecto educativo de barrio en un entorno socioeconómico desfavorecido : desde cero años hasta la escuela de adultos'.

Resumen basado en el de la autora

El Grupo Zero.

Se hace un breve repaso de la historia del Grupo Zero desde sus inicios en 1975, presentando las líneas básicas de su trabajo, entre las cuales destaca la búsqueda de maneras que permitan al alumnado vivir la actividad matemática en contextos o situaciones significativas, en un ambiente de trabajo que favorezca su implicación en el propio aprendizaje. También se valora la pertenencia al Grupo Zero como una ocasión excepcional de autoformación en la propia aula.

SF e Animé : os Monstros Encantadores do Ground Zero

O fascínio do poder de dotar de vida ao que está inanimado talvez possa ajudar a revelar o encanto que sentimos quando os objectos fixos se começam a mover e a desenvolver coreografias cheias de vida. Na animé, a técnica do desenho tornou-se o processo ideal para explorar estes temas por ser mais fácil desenhar figuras monstruosas do que construir personagens, naves ou cenários futuristas para o cinema live-action. Após a II Grande Guerra, no momento inicial da reconstrução do Japão, o Ground Zero, coincide com o desenvolvimento de uma cultura pop na qual os desenhos manga e a animé se tornaram referências fundamentais. Iremos verificar como uma das importantes particularidades de séries de animação japonesa é a exploração de imaginários SF onde o atómico é encanto monstruoso, que se controla ou pelo qual se é controlado. Dando especial destaque às séries de televisão Prince Planet (Sato Okura, 1965), Gigantor (Mitsuteru Yokoyama, 1963) ou Astro Boy (Osamu Tezuka, 1963), iremos demonstrar que pela componente técnica ou visual da animação a animé é um modelo específico de estudo para tentar contextualizar a atracção humana por mundos controlados por máquinas, pela manipulação genética ou pela possibilidade de uma paisagem cyborg.

La relación entre lo político y lo estético en el teatro quiteño: estudio de caso de 7 grupos Malayerba, Zero no Zero, Cronopio, Patio de Comedias, Contraelviento, Callejón del Agua y Espada de Madera

Tiene por objetivo analizar la relación existente entre lo político y lo estético en el teatro quiteño. Dicha relación la quiero analizar a partir de constatar los cambios producidos en el teatro quiteño luego de la década de los noventa, cambios cuyo eje básico, a mi modo de ver, se expresa en el paso del fevor de lo político-militante hacía temas más teatrales. Para el momento actual, es posible ver ya qué forma fueron tomando y por dónde se fueron resolviendo las inquietudes que llevan a los teatreros a plantearse ese cambio de perspectiva. Para enfrentar la pregunta citada voy a hacer un análisis de los montajes de los espectáculos desarrollados en el año 2007 de los siguientes grupos teatrales quiteños: Zero no Zero, Cronopio, Elenco del Patio de Comedias, Malayerba, Contraelviento, Callejón del Agua y Espada de Madera. Dicho análisis lo hago a partir de revisar el contexto en el que se desarrollan y apoyándome del cuestionario desarrollado por Patrice Pavis en su libro El análisis de los espectáculos. Para analizar la relación entre lo político y lo estético en el teatro en Quito que se evidencia en los montajes actuales, voy a desarrollar las categorías teóricas que Javier Sanjinés elabora, a partir de las reflexiones de Walter Benjamin, para indagar lo nacional en Bolivia en las artes visuales. Cruzo dichas categorías con las reflexiones de Augusto Boal en el libro El Teatro del Oprimido para así completar un cuerpo teórico que me permita encontrar la relación entre lo político y lo estético en el teatro.

The counterpropagating Rossby wave perspective on Kelvin Helmholtz instability as a limiting case of a Rayleigh shear layer with zero width

The Kelvin Helmholtz (KH) problem, with zero stratification, is examined as a limiting case of the Rayleigh model of a single shear layer whose width tends to zero. The transition of the Rayleigh modal dispersion relation to the KH one, as well as the disappearance of the supermodal transient growth in the KH limit, are both rationalized from the counterpropagating Rossby wave perspective.

Improvements to the accuracy of measurements of NO2 by zenith-sky visible spectrometers II: errors in zero using a more complete chemical model

Using a flexible chemical box model with full heterogeneous chemistry, intercepts of chemically modified Langley plots have been computed for the 5 years of zenith-sky NO2 data from Faraday in Antarctica (65°S). By using these intercepts as the effective amount in the reference spectrum, drifts in zero of total vertical NO2 were much reduced. The error in zero of total NO2 is ±0.03×1015 moleccm−2 from one year to another. This error is small enough to determine trends in midsummer and any variability in denoxification between midwinters. The technique also suggests a more sensitive method for determining N2O5 from zenith-sky NO2 data.

A covariate adjustment for zero-truncated approaches to estimating the size of hidden and elusive populations

In this paper we consider the estimation of population size from onesource capture–recapture data, that is, a list in which individuals can potentially be found repeatedly and where the question is how many individuals are missed by the list. As a typical example, we provide data from a drug user study in Bangkok from 2001 where the list consists of drug users who repeatedly contact treatment institutions. Drug users with 1, 2, 3, . . . contacts occur, but drug users with zero contacts are not present, requiring the size of this group to be estimated. Statistically, these data can be considered as stemming from a zero-truncated count distribution.We revisit an estimator for the population size suggested by Zelterman that is known to be robust under potential unobserved heterogeneity. We demonstrate that the Zelterman estimator can be viewed as a maximum likelihood estimator for a locally truncated Poisson likelihood which is equivalent to a binomial likelihood. This result allows the extension of the Zelterman estimator by means of logistic regression to include observed heterogeneity in the form of covariates. We also review an estimator proposed by Chao and explain why we are not able to obtain similar results for this estimator. The Zelterman estimator is applied in two case studies, the first a drug user study from Bangkok, the second an illegal immigrant study in the Netherlands. Our results suggest the new estimator should be used, in particular, if substantial unobserved heterogeneity is present.

A revised Tobit procedure for mitigating bias in the presence of non-zero censoring with an application to milk-market participation in the Ethiopian highlands

Fixed transactions costs that prohibit exchange engender bias in supply analysis due to censoring of the sample observations. The associated bias in conventional regression procedures applied to censored data and the construction of robust methods for mitigating bias have been preoccupations of applied economists since Tobin [Econometrica 26 (1958) 24]. This literature assumes that the true point of censoring in the data is zero and, when this is not the case, imparts a bias to parameter estimates of the censored regression model. We conjecture that this bias can be significant; affirm this from experiments; and suggest techniques for mitigating this bias using Bayesian procedures. The bias-mitigating procedures are based on modifications of the key step that facilitates Bayesian estimation of the censored regression model; are easy to implement; work well in both small and large samples; and lead to significantly improved inference in the censored regression model. These findings are important in light of the widespread use of the zero-censored Tobit regression and we investigate their consequences using data on milk-market participation in the Ethiopian highlands. (C) 2004 Elsevier B.V. All rights reserved.

Extending Zelterman’s approach for robust estimation of population size to zero-truncated clustered data

Estimation of population size with missing zero-class is an important problem that is encountered in epidemiological assessment studies. Fitting a Poisson model to the observed data by the method of maximum likelihood and estimation of the population size based on this fit is an approach that has been widely used for this purpose. In practice, however, the Poisson assumption is seldom satisfied. Zelterman (1988) has proposed a robust estimator for unclustered data that works well in a wide class of distributions applicable for count data. In the work presented here, we extend this estimator to clustered data. The estimator requires fitting a zero-truncated homogeneous Poisson model by maximum likelihood and thereby using a Horvitz-Thompson estimator of population size. This was found to work well, when the data follow the hypothesized homogeneous Poisson model. However, when the true distribution deviates from the hypothesized model, the population size was found to be underestimated. In the search of a more robust estimator, we focused on three models that use all clusters with exactly one case, those clusters with exactly two cases and those with exactly three cases to estimate the probability of the zero-class and thereby use data collected on all the clusters in the Horvitz-Thompson estimator of population size. Loss in efficiency associated with gain in robustness was examined based on a simulation study. As a trade-off between gain in robustness and loss in efficiency, the model that uses data collected on clusters with at most three cases to estimate the probability of the zero-class was found to be preferred in general. In applications, we recommend obtaining estimates from all three models and making a choice considering the estimates from the three models, robustness and the loss in efficiency. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Sparse kernel density estimation technique based on zero-norm constraint

A sparse kernel density estimator is derived based on the zero-norm constraint, in which the zero-norm of the kernel weights is incorporated to enhance model sparsity. The classical Parzen window estimate is adopted as the desired response for density estimation, and an approximate function of the zero-norm is used for achieving mathemtical tractability and algorithmic efficiency. Under the mild condition of the positive definite design matrix, the kernel weights of the proposed density estimator based on the zero-norm approximation can be obtained using the multiplicative nonnegative quadratic programming algorithm. Using the -optimality based selection algorithm as the preprocessing to select a small significant subset design matrix, the proposed zero-norm based approach offers an effective means for constructing very sparse kernel density estimates with excellent generalisation performance.

Performance comparison of the optimal and the zero-forcing beamforming algorithms under practical conditions

The optimal and the zero-forcing beamformers are two commonly used algorithms in the subspace-based blind beamforming technology. The optimal beamformer is regarded as the algorithm with the best output SINR. The zero-forcing algorithm emphasizes the co-channel interference cancellation. This paper compares the performance of these two algorithms under some practical conditions: the effect of the finite data length and the existence of the angle estimation error. The investigation reveals that the zero-forcing algorithm can be more robust in the practical environment than the optimal algorithm.