4 research outputs found

    Entropy inference and the James-Stein estimator, with application to nonlinear gene association networks

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    We present a procedure for effective estimation of entropy and mutual information from small-sample data, and apply it to the problem of inferring high-dimensional gene association networks. Specifically, we develop a James-Stein-type shrinkage estimator, resulting in a procedure that is highly efficient statistically as well as computationally. Despite its simplicity, we show that it outperforms eight other entropy estimation procedures across a diverse range of sampling scenarios and data-generating models, even in cases of severe undersampling. We illustrate the approach by analyzing E. coli gene expression data and computing an entropy-based gene-association network from gene expression data. A computer program is available that implements the proposed shrinkage estimator.Comment: 18 pages, 3 figures, 1 tabl

    Integration of Multiple Temporal Qualitative Probabilistic Networks in Time Series Environments

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    Abstract: The integration of uncertain information from different time sources is a crucial issue in various applications. In this paper, we propose an integration method of multiple Temporal Qualitative Probabilistic Networks (TQPNs) in time series environments. First, we present the method for learning TQPN from time series data. The TQPN's structure is constructed using Dynamic Bayesian Networks learning based on Markov Chain Monte Carlo. Furthermore, the corresponding qualitative influences are obtained by the conditional probabilities. Secondly, based on rough set theory, we integrate multiple TQPNs into a single QPN that preserves as much information as possible. Specifically, we take the rough-set-based dependency degree as the strength of qualitative influence, and then make the rules to solve the ambiguities reduction and cycles deletion problems which arise from the integration of different TQPNs. Finally, we verify the feasibility of the integration method by the simulation experiments

    Effects of life events and attitudes on vehicle transactions: A dynamic Bayesian network approach

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    Individual and household life events are interdependent and influence mobility-related decisions at different levels over time. This paper developed an integrated dynamic model to capture the interdependences among life events, with a special focus on vehicle transactions. Particular attention was paid to the inclusion of vehicles’ characteristics such as the age, fuel type, and size of cars, which are pertinent to emission forecast. A dynamic Bayesian network (DBN), containing individual and household characteristics and latent attitudes toward car ownership and use alongside life events, was employed to study the interdependences. The temporal relationships among life events and lead-lag effects were also captured in the DBN. The longitudinal survey data “the Netherlands Mobility Panel (MPN)” from 2013 to 2018 was used to train and test the DBN. The analysis results confirm the dynamic interdependences between vehicle transactions and other life events and reveal noticeable associations between attitudes and purchase decisions. It is found that several life events (e.g., “Birth of a baby”, “Marital status change”) have concurrent or varied lag-effects on vehicle transaction decisions. The validation indicates that the proposed DBN approach has a high predictive accuracy of vehicle transaction decisions and other life events
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