2,929 research outputs found

    A Simple Approach to Constructing Quasi-Sudoku-based Sliced Space-Filling Designs

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    Sliced Sudoku-based space-filling designs and, more generally, quasi-sliced orthogonal array-based space-filling designs are useful experimental designs in several contexts, including computer experiments with categorical in addition to quantitative inputs and cross-validation. Here, we provide a straightforward construction of doubly orthogonal quasi-Sudoku Latin squares which can be used to generate sliced space-filling designs which achieve uniformity in one and two-dimensional projections for both the full design and each slice. A construction of quasi-sliced orthogonal arrays based on these constructed doubly orthogonal quasi-Sudoku Latin squares is also provided and can, in turn, be used to generate sliced space-filling designs which achieve uniformity in one and two-dimensional projections for the full design and and uniformity in two-dimensional projections for each slice. These constructions are very practical to implement and yield a spectrum of design sizes and numbers of factors not currently broadly available.Comment: 15 pages, 9 figure

    Accuracy of multi-point boundary crossing time analysis

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    Recent multi-spacecraft studies of solar wind discontinuity crossings using the timing (boundary plane triangulation) method gave boundary parameter estimates that are significantly different from those of the well-established single-spacecraft minimum variance analysis (MVA) technique. A large survey of directional discontinuities in Cluster data turned out to be particularly inconsistent in the sense that multi-point timing analyses did not identify any rotational discontinuities (RDs) whereas the MVA results of the individual spacecraft suggested that RDs form the majority of events. To make multi-spacecraft studies of discontinuity crossings more conclusive, the present report addresses the accuracy of the timing approach to boundary parameter estimation. Our error analysis is based on the reciprocal vector formalism and takes into account uncertainties both in crossing times and in the spacecraft positions. A rigorous error estimation scheme is presented for the general case of correlated crossing time errors and arbitrary spacecraft configurations. Crossing time error covariances are determined through cross correlation analyses of the residuals. The principal influence of the spacecraft array geometry on the accuracy of the timing method is illustrated using error formulas for the simplified case of mutually uncorrelated and identical errors at different spacecraft. The full error analysis procedure is demonstrated for a solar wind discontinuity as observed by the Cluster FGM instrument

    Political Success and the Media

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    How have different media affected the linguistic performativity of the most prominent American politicians throughout history? How have different types of media allowed certain linguistic features to flourish, and others to fail? I address these question’s through a diachronic analysis of three different periods of American history as well as an investigation into effective linguistic features that manifest over the radio, through television, and on social media. In addition, I confront the myth that there is a relationship between reading level of speech determined by the Flesch-Kincaid algorithm and success as an orator. I find relationships between linguistic features unique to the media through which it is presented and conclude on how that affects the overall expertise of the candidate, but find no relationship between Flesch-Kincaid reading level and expertise

    Non-Linear Deformations of Liquid-Liquid Interfaces Induced by Electromagnetic Radiation Pressure

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    The idea of working with a near-critical phase-separated liquid mixture whereby the surface tension becomes weak, has recently made the field of laser manipulation of liquid interfaces a much more convenient tool in practice. The deformation of interfaces may become as large as several tenths of micrometers, even with the use of conventional laser power. This circumstance necessitates the use of nonlinear geometrical theory for the description of surface deformations. The present paper works out such a theory, for the surface deformation under conditions of axial symmetry and stationarity. Good agreement is found with the experimental results of Casner and Delville [A. Casner and J. P. Delville, Phys. Rev. Lett. {\bf 87}, 054503 (2001); Opt. Lett. {\bf 26}, 1418 (2001); Phys. Rev. Lett. {\bf 90}, 144503 (2003)], in the case of moderate power or a broad laser beam. In the case of large power and a narrow beam, corresponding to surface deformations of about 50 micrometers or higher, the theory is found to over-predict the deformation. Possible explanations of this discrepancy are discussed.Comment: RevTeX4, 19 pages, 4 figures. Sec. IIIB rewritten, 4 new references. To appear in Phys. Rev.

    Second-Order Accurate Inference on Simple, Partial, and Multiple Correlations

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    This article develops confidence interval procedures for functions of simple, partial, and squared multiple correlation coefficients. It is assumed that the observed multivariate data represent a random sample from a distribution that possesses infinite moments, but there is no requirement that the distribution be normal. The coverage error of conventional one-sided large sample intervals decreases at rate 1√n as n increases, where n is an index of sample size. The coverage error of the proposed intervals decreases at rate 1/n as n increases. The results of a simulation study that evaluates the performance of the proposed intervals is reported and the intervals are illustrated on a real data set

    Extramural English, with an emphasis on gaming, and Norwegian National test scores in English, 8th grade

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    In an increasingly globalized world, digital gaming has emerged, and learning English as a second language has changed towards being a language easily accessible in students out-of-school contexts. This thesis investigates if there are significant interactions between the participants extramural English language activities and the results on the NNT in English, 8th grade. English is a global language and functions as a lingua franca in entertainment such as gaming, streaming services and social media. In our research, data was collected from six 8th grade classes in Norwegian lower secondary schools through a quantitative research method, using a questionnaire and the results from the Norwegian National test in English, 8th grade. The questionnaire contains information about the participants background, gaming, and media habits and was linked to the participants results on the Norwegian National test in English. All analyses were computed using the software platform IBM SPSS statistics 28 and are presented through descriptive and inferential statistics. Significant interactions were found between extramural English language activities and the score of level on Norwegian National test in English 8th grade. Significant interactions were also found when dividing the group in gender. Tendencies show that a majority of the participants meet English content through extramural activities. Gender group differences were also found but vary in forms of what extramural activity the students engage in, in addition to differences to the extent they meet input, use/produce output and interact in L2

    Jobs and technology in general equilibrium: A three-elasticities approach

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    The impact of technological progress on jobs and wages has been subject to much empirical and some theoretical work. However, most of this literature has not addressed the general equilibrium interplay between the productive factors that are affected, the sectors in which these factors are used, and the consequent changes in the structure of employment and factor returns. This paper draws on tools from general equilibrium trade theory to provide an integrated approach to these issues. The analysis centres around three key elasticities linking technological change to jobs – the jobs-displacing substitution effect, the job-creating demand effect, and the general-equilibrium effects, through which factors are reallocated between sectors. The results highlight the role of relative factor intensities and the importance of openness in determining the effects of technology on jobs, wages, and structural change. The implications of interaction between non-tradable and tradable sectors are analysed
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