601,340 research outputs found

    PhyloPars: estimation of missing parameter values using phylogeny

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    A wealth of information on metabolic parameters of a species can be inferred from observations on species that are phylogenetically related. Phylogeny-based information can complement direct empirical evidence, and is particularly valuable if experiments on the species of interest are not feasible. The PhyloPars web server provides a statistically consistent method that combines an incomplete set of empirical observations with the species phylogeny to produce a complete set of parameter estimates for all species. It builds upon a state-of-the-art evolutionary model, extended with the ability to handle missing data. The resulting approach makes optimal use of all available information to produce estimates that can be an order of magnitude more accurate than ad-hoc alternatives. Uploading a phylogeny and incomplete feature matrix suffices to obtain estimates of all missing values, along with a measure of certainty. Real-time cross-validation provides further insight in the accuracy and bias expected for estimated values. The server allows for easy, efficient estimation of metabolic parameters, which can benefit a wide range of fields including systems biology and ecology. PhyloPars is available at: http://www.ibi.vu.nl/programs/phylopars/

    PERANCANGAN SISTEM INFORMASI AKUNTANSI (Studi kasus pada CV. MITRA TANINDO)

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    This study examined the Accounting Information System Design in CV. Mitra Tanindo. This research was conducted to determine the good and the weakness of Accounting Information System in the company and provide recommendations to the Accounting Information Systems. This study uses a case study approach. Method of data collection is done by direct observation in the object of research, namely CV. Mitra Tanindo to obtain data suitable data collection techniques. The data used in this research is the primary data is data obtained directly from the company through interviews, observation and documentation was processed and concluded. The analysis used in this study is a qualitative analysis; the analysis carried out by finding strengths and weaknesses of Accounting Information Systems is in the company. The result of this research is there are still some weaknesses were found. At the organizational structure, the overlap in the administrative tasks. Accounting Information System Goods Purchase of Trade, there is no document request merchandise purchase. Sales Accounting Information System of Cash, the transportation section does not accept Cash Sign Documents evidence that can not be compared with cash sales invoice before the goods delivered to the buyer. Accounting Information System of Credit Sales, Credit Sales Invoice Document incomplete. Payroll Accounting Information Systems ie, No Statement of Wages as payroll documents for employees. Based on these weaknesses, researchers gave suggestions for the design of CV. Accounting Information Systems. Mitra Tanindo. Organizational Structure of the Company, Making purchasing functions and sales functions. Accounting Information System Goods Purchase of Trade, Letter of Inquiry Making a document to record the purchase of merchandise required. Accounting Information System of Cash Sales, received the document transport section Invoice Cash Sales-2 and receive Cash Sales Invoice-1 and Evidence from the Treasury in order to transport compared before sending the goods to the buyer. Accounting Information System of Credit Sales, Cash Sales Invoice five copies made so that the credit-related sales to get this document. Payroll Accounting Information System is, making the Declaration of Wages. Keywords: Accounting Information Systems, Purchase of merchandise, merchandise supply records, merchandise sales and payroll

    Multi-view constrained clustering with an incomplete mapping between views

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    Multi-view learning algorithms typically assume a complete bipartite mapping between the different views in order to exchange information during the learning process. However, many applications provide only a partial mapping between the views, creating a challenge for current methods. To address this problem, we propose a multi-view algorithm based on constrained clustering that can operate with an incomplete mapping. Given a set of pairwise constraints in each view, our approach propagates these constraints using a local similarity measure to those instances that can be mapped to the other views, allowing the propagated constraints to be transferred across views via the partial mapping. It uses co-EM to iteratively estimate the propagation within each view based on the current clustering model, transfer the constraints across views, and then update the clustering model. By alternating the learning process between views, this approach produces a unified clustering model that is consistent with all views. We show that this approach significantly improves clustering performance over several other methods for transferring constraints and allows multi-view clustering to be reliably applied when given a limited mapping between the views. Our evaluation reveals that the propagated constraints have high precision with respect to the true clusters in the data, explaining their benefit to clustering performance in both single- and multi-view learning scenarios

    Global estimation of child mortality using a Bayesian B-spline Bias-reduction model

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    Estimates of the under-five mortality rate (U5MR) are used to track progress in reducing child mortality and to evaluate countries' performance related to Millennium Development Goal 4. However, for the great majority of developing countries without well-functioning vital registration systems, estimating the U5MR is challenging due to limited data availability and data quality issues. We describe a Bayesian penalized B-spline regression model for assessing levels and trends in the U5MR for all countries in the world, whereby biases in data series are estimated through the inclusion of a multilevel model to improve upon the limitations of current methods. B-spline smoothing parameters are also estimated through a multilevel model. Improved spline extrapolations are obtained through logarithmic pooling of the posterior predictive distribution of country-specific changes in spline coefficients with observed changes on the global level. The proposed model is able to flexibly capture changes in U5MR over time, gives point estimates and credible intervals reflecting potential biases in data series and performs reasonably well in out-of-sample validation exercises. It has been accepted by the United Nations Inter-agency Group for Child Mortality Estimation to generate estimates for all member countries.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS768 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

    On large-scale diagonalization techniques for the Anderson model of localization

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    We propose efficient preconditioning algorithms for an eigenvalue problem arising in quantum physics, namely the computation of a few interior eigenvalues and their associated eigenvectors for large-scale sparse real and symmetric indefinite matrices of the Anderson model of localization. We compare the Lanczos algorithm in the 1987 implementation by Cullum and Willoughby with the shift-and-invert techniques in the implicitly restarted Lanczos method and in the Jacobiā€“Davidson method. Our preconditioning approaches for the shift-and-invert symmetric indefinite linear system are based on maximum weighted matchings and algebraic multilevel incomplete LDLT factorizations. These techniques can be seen as a complement to the alternative idea of using more complete pivoting techniques for the highly ill-conditioned symmetric indefinite Anderson matrices. We demonstrate the effectiveness and the numerical accuracy of these algorithms. Our numerical examples reveal that recent algebraic multilevel preconditioning solvers can accelerate the computation of a large-scale eigenvalue problem corresponding to the Anderson model of localization by several orders of magnitude

    The Matrix Ridge Approximation: Algorithms and Applications

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    We are concerned with an approximation problem for a symmetric positive semidefinite matrix due to motivation from a class of nonlinear machine learning methods. We discuss an approximation approach that we call {matrix ridge approximation}. In particular, we define the matrix ridge approximation as an incomplete matrix factorization plus a ridge term. Moreover, we present probabilistic interpretations using a normal latent variable model and a Wishart model for this approximation approach. The idea behind the latent variable model in turn leads us to an efficient EM iterative method for handling the matrix ridge approximation problem. Finally, we illustrate the applications of the approximation approach in multivariate data analysis. Empirical studies in spectral clustering and Gaussian process regression show that the matrix ridge approximation with the EM iteration is potentially useful
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