Bayesian estimation of the spatial Durbin error model with an application to voter turnout in the 2004 presidential election

The potential for spatial dependence in models of voter turnout, although plausible from a theoretical perspective, has not been adequately addressed in the literature. Using recent advances in Bayesian computation, we formulate and estimate the previously unutilized spatial Durbin error model and apply this model to the question of whether spillovers and unobserved spatial dependence in voter turnout matters from an empirical perspective. Formal Bayesian model comparison techniques are employed to compare the normal linear model, the spatially lagged X model (SLX), the spatial Durbin model, and the spatial Durbin error model. The results overwhelmingly support the spatial Durbin error model as the appropriate empirical model.

Market transparency and collusion: on the UK agricultural tractor registration exchange

We review the decision by the European Commission in the case of the UK Agricultural Registration Exchange. We propose a theoretical model, offering a basis for some of the intuitive arguments used by the Commission on the anti-competitive role of information exchange in the case of price and non price collusion. Market transparency on non price data is shown to be a collusion facilitating device which may achieve stability in otherwise unstable cartels.

An ASIFT-based local registration method for satellite imagery

Imagery registration is a fundamental step, which greatly affects later processes in image mosaic, multi-spectral image fusion, digital surface modelling, etc., where the final solution needs blending of pixel information from more than one images. It is highly desired to find a way to identify registration regions among input stereo image pairs with high accuracy, particularly in remote sensing applications in which ground control points (GCPs) are not always available, such as in selecting a landing zone on an outer space planet. In this paper, a framework for localization in image registration is developed. It strengthened the local registration accuracy from two aspects: less reprojection error and better feature point distribution. Affine scale-invariant feature transform (ASIFT) was used for acquiring feature points and correspondences on the input images. Then, a homography matrix was estimated as the transformation model by an improved random sample consensus (IM-RANSAC) algorithm. In order to identify a registration region with a better spatial distribution of feature points, the Euclidean distance between the feature points is applied (named the S criterion). Finally, the parameters of the homography matrix were optimized by the Levenberg–Marquardt (LM) algorithm with selective feature points from the chosen registration region. In the experiment section, the Chang’E-2 satellite remote sensing imagery was used for evaluating the performance of the proposed method. The experiment result demonstrates that the proposed method can automatically locate a specific region with high registration accuracy between input images by achieving lower root mean square error (RMSE) and better distribution of feature points.

Candidate Quality and Voter Response in U.S. House Elections

We propose and test the implications of a two-dimensional concept of candidate quality in U.S. House elections. Strategic quality is composed of the skills and resources necessary to wage an effective campaign; personal quality is composed of the characteristics most ordinary citizens value in their leaders and representatives, such as personal integrity and dedication to public service. We employ district informants in studies of the 1998 and 2002 congressional elections to measure these qualities in candidates, and we merge mass survey data with the district informant indicators to assess constituents’ awareness and evaluation of House candidates, and voting choice. We find that awareness tends to be responsive to candidates’ strategic quality, and that incumbent evaluation is remarkably responsive to variation in personal quality, even taking into account the quality of challenger emergence. These and other findings appear to support a more positive view of citizen capacity than is common in the congressional elections literature, especially in light of the electoral security of House incumbents.

Voter turnout, inflation, and the politics of macroeconomic policy: an empirical essay

This thesis tests some hypotheses regarding the impact of voter turnout on inflation on the assumption that macroeconomic policies depend on voters’ and politicians’ preferences. The work’s empirical basis includes data from 111 nations from the developing world, covering the period from 1978 to 2000. Its main finding indicates that increases in voter turnout co-vary with higher inflation rates, all else held constant.

Neighborhood information exchange and voter participation : an experimental study

We study the effect of social embeddedness on voter turnout by investigating the role of information about other voters’ decisions. We do so in a participation game, where some voters (‘receivers’) are told about some other voters’ (‘senders’) turnout decision at a first stage of the game. Cases are distinguished where the voters support the same or different candidates or where they are uncertain about each other’s preferences. Our experimental results show that such information matters. Participation is much higher when information is exchanged than when it is not. Senders strategically try to use their first mover position and some receivers respond to this.

A Theory of voter experimentation in repeated elections

Nesse artigo, eu desenvolvo e analiso um modelo de dois perí odos em que dois polí ticos competem pela preferência de um eleitor representativo, que sabe quão benevolente é um dos polí ticos mas é imperfeitamente informado sobre quão benevolente é o segundo polí tico. O polí tico conhecido é interpretado como um incumbente de longo prazo, ao passo que o polí tico desconhecido é interpretado como um desa fiante menos conhecido. É estabelecido que o mecanismo de provisão de incentivos inerente às elei cões - que surge através da possibilidade de não reeleger um incumbente - e considerações acerca de aquisi cão de informa cão por parte do eleitor se combinam de modo a determinar que em qualquer equilí brio desse jogo o eleitor escolhe o polí tico desconhecido no per íodo inicial do modelo - uma a cão à qual me refi ro como experimenta cão -, fornecendo assim uma racionaliza cão para a não reelei cão de incumbentes longevos. Especifi camente, eu mostro que a decisão do eleitor quanto a quem eleger no per odo inicial se reduz à compara cão entre os benefí cios informacionais de escolher o polí tico desconhecido e as perdas econômicas de fazê-lo. Os primeiros, que capturam as considera cões relacionadas à aquisi cão de informa cão, são mostrados serem sempre positivos, ao passo que as últimas, que capturam o incentivo à boa performance, são sempre não-negativas, implicando que é sempre ótimo para o eleitor escolher o polí tico desconhecido no per íodo inicial.

Oral cavity evaluation and dental chart registration of coati (Nasua nasua) in captivity

The aims of this study were to develop a dental chart evaluate any oral cavity disease, develop gypsum models the dental arches, and to register the occlusions found in coatis (Nasua nasua) in captivity. Formulation of the dental chart was assisted by intraoral radiographs from the head of an adult coati cadaver of the same species with the following dental formula: I 3/3, C 1/1, P 4/3, M 2/2. Seven live coatis of the Nasua nasua species were evaluated. Five of the seven coatis presented with various dental abnormalities as follows: dental plaque (71.4 %), gingivitis (71.4 %), periodontitis (57.1 %), dental stain (42.9 %), dental abrasion (57.1 %), dental fracture (57.1 %), pulp exposure (42.9 %), malocclusion (5 7.1 %) and supernumerary teeth (14.2 %).

Fast sequential multi-element determination of Ca, Mg, K, Cu, Fe, Mn and Zn for foliar diagnosis using high-resolution continuum source flame atomic absorption spectrometry: Feasibility of secondary lines, side pixel registration and least-squares background correction

The fast sequential multi-element determination of Ca, Mg, K, Cu, Fe, Mn and Zn in plant tissues by high-resolution continuum source flame atomic absorption spectrometry is proposed. For this, the main lines for Cu (324.754 nm), Fe (248.327 nm), Mn (279.482 nm) and Zn (213.857 nm) were selected, and the secondary lines for Ca (239.856 nm), Mg (202.582 nm) and K (404.414 nm) were evaluated. The side pixel registration approach was studied to reduce sensitivity and extend the linear working range for Mg by measuring at wings (202.576 nm; 202.577 nm; 202.578 nm; 202.580 nm: 202.585 nm; 202.586 nm: 202.587 nm; 202.588 nm) of the secondary line. The interference caused by NO bands on Zn at 213.857 nm was removed using the least-squares background correction. Using the main lines for Cu, Fe, Mn and Zn, secondary lines for Ca and K, and line wing at 202.588 nm for Mg, and 5 mL min(-1) sample flow-rate, calibration curves in the 0.1-0.5 mg L-1 Cu, 0.5-4.0 mg L-1 Fe, 0.5-4.0 mg L-1 Mn, 0.2-1.0 mg L-1 Zn, 10.0-100.0 mg L-1 Ca, 5.0-40.0 mg L-1 Mg and 50.0-250.0 mg L-1 K ranges were consistently obtained. Accuracy and precision were evaluated after analysis of five plant standard reference materials. Results were in agreement at a 95% confidence level (paired t-test) with certified values. The proposed method was applied to digests of sugar-cane leaves and results were close to those obtained by line-source flame atomic absorption spectrometry. Recoveries of Ca, Mg, K, Cu, Fe, Mn and Zn in the 89-103%, 84-107%, 87-103%, 85-105%, 92-106%, 91-114%, 96-114% intervals, respectively, were obtained. The limits of detection were 0.6 mg L-1 Ca, 0.4 mg L-1 Mg, 0.4 mg L-1 K, 7.7 mu g L-1 Cu, 7.7 mu g L-1 Fe, 1.5 mu g L-1 Mn and 5.9 mu g L-1 Zn. (C) 2009 Elsevier B.V. All rights reserved.

Image registration and image interpolation in volume rendering of cross sections

We outline a method for registration of images of cross sections using the concepts of The Generalized Hough Transform (GHT). The approach may be useful in situations where automation should be a concern. To overcome known problems of noise of traditional GHT we have implemented a slight modified version of the basic algorithm. The modification consists of eliminating points of no interest in the process before the application of the accumulation step of the algorithm. This procedure minimizes the amount of accumulation points while reducing the probability of appearing of spurious peaks. Also, we apply image warping techniques to interpolate images among cross sections. This is needed where the distance of samples between sections is too large. Then it is suggested that the step of registration with GHT can help the interpolation automation by simplifying the correspondence between points of images. Some results are shown.

Construction of ethics in clinical research - Clinical trials registration

Scientific development that has been achieved through decades finds in clinical research a great possibility of translating findings to human health application. Evidence given by clinical trials allows everyone to have access to the best health services. However, the millionaire world of pharmaceutical industries has stained clinical research with doubt and improbability. Study results (fruits of controlled clinical trials) and scientific publications (selective, manipulated and with wrong conclusions) led to an inappropriate clinical practice, favoring the involved economic aspect. In 2005, the International Committee of Medical Journal Editors (ICMJE), supported by the World Association of Medical Editors, started demanding as a requisite for publication that all clinical trials be registered at the database ClinicalTrials.gov. In 2006, the World Health Organization (WHO) created the International Clinical Trial Registry Platform (ICTRP), which gathers several registry centers from all over the world, and required that all researchers and pharmaceutical industries register clinical trials. Such obligatory registration has progressed and will extend to all scientific journals indexed in all worldwide databases. Registration of clinical trials means another step of clinical research towards transparency, ethics and impartiality, resulting in real evidence to the forthcoming changes in clinical practice as well as in the health situation.

Assessment of color fidelity of several composite resins compared to their Vita Classical shade registration

This study compared the color fidelity of different composite resins with their registration in the Vita Classical Shade Guide. Using a prefabricated Teflon mold, 120 specimens were divided into four groups fn - 30), according to the resin tested. Three subgroups (a = 10) were prepared for each resin group; these subgroups tested enamel shade, dentin shade, and enamel and dentin shade. Three measurements were performed to verily whether the tooth shade matched that of the Vita Classical Shade Guide. The color was evaluated and the shade variations were calculated. The data were submitted to a three-way AN OVA test (time, color match, and composite type), followed by Tukey's test. It was concluded that all composite resins showed color differences in relation to the Vita Classical Shade Guide.