56 research outputs found
Analysis of Collectivism and Egoism Phenomena within the Context of Social Welfare
Comparative benefits provided by the basic social strategies including
collectivism and egoism are investigated within the framework of democratic
decision-making. In particular, we study the mechanism of growing "snowball" of
cooperation.Comment: 12 pages, 5 figures. Translated from Russian. Original Russian Text
published in Problemy Upravleniya, 2008, No. 4, pp. 30-3
The Projection Method for Reaching Consensus and the Regularized Power Limit of a Stochastic Matrix
In the coordination/consensus problem for multi-agent systems, a well-known
condition of achieving consensus is the presence of a spanning arborescence in
the communication digraph. The paper deals with the discrete consensus problem
in the case where this condition is not satisfied. A characterization of the
subspace of initial opinions (where is the influence matrix) that
\emph{ensure} consensus in the DeGroot model is given. We propose a method of
coordination that consists of: (1) the transformation of the vector of initial
opinions into a vector belonging to by orthogonal projection and (2)
subsequent iterations of the transformation The properties of this method
are studied. It is shown that for any non-periodic stochastic matrix the
resulting matrix of the orthogonal projection method can be treated as a
regularized power limit of Comment: 19 pages, 2 figure
Coordination in multiagent systems and Laplacian spectra of digraphs
Constructing and studying distributed control systems requires the analysis
of the Laplacian spectra and the forest structure of directed graphs. In this
paper, we present some basic results of this analysis partially obtained by the
present authors. We also discuss the application of these results to
decentralized control and touch upon some problems of spectral graph theory.Comment: 15 pages, 2 figures, 40 references. To appear in Automation and
Remote Control, Vol.70, No.3, 200
Scuba:Scalable kernel-based gene prioritization
Abstract Background The uncovering of genes linked to human diseases is a pressing challenge in molecular biology and precision medicine. This task is often hindered by the large number of candidate genes and by the heterogeneity of the available information. Computational methods for the prioritization of candidate genes can help to cope with these problems. In particular, kernel-based methods are a powerful resource for the integration of heterogeneous biological knowledge, however, their practical implementation is often precluded by their limited scalability. Results We propose Scuba, a scalable kernel-based method for gene prioritization. It implements a novel multiple kernel learning approach, based on a semi-supervised perspective and on the optimization of the margin distribution. Scuba is optimized to cope with strongly unbalanced settings where known disease genes are few and large scale predictions are required. Importantly, it is able to efficiently deal both with a large amount of candidate genes and with an arbitrary number of data sources. As a direct consequence of scalability, Scuba integrates also a new efficient strategy to select optimal kernel parameters for each data source. We performed cross-validation experiments and simulated a realistic usage setting, showing that Scuba outperforms a wide range of state-of-the-art methods. Conclusions Scuba achieves state-of-the-art performance and has enhanced scalability compared to existing kernel-based approaches for genomic data. This method can be useful to prioritize candidate genes, particularly when their number is large or when input data is highly heterogeneous. The code is freely available at https://github.com/gzampieri/Scuba
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