Dynamic Bayesian network

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Dynamic Bayesian Network composed by 3 variables. Reseau bayesien dynamique.svg
Dynamic Bayesian Network composed by 3 variables.
Bayesian Network developed on 3 time steps. Reseau bayesien 3t.svg
Bayesian Network developed on 3 time steps.
Simplified Dynamic Bayesian Network. All the variables do not need to be duplicated in the graphical model, but they are dynamic, too. Reseau bayesien simplifie.svg
Simplified Dynamic Bayesian Network. All the variables do not need to be duplicated in the graphical model, but they are dynamic, too.

A dynamic Bayesian network (DBN) is a Bayesian network (BN) which relates variables to each other over adjacent time steps.

Contents

History

A dynamic Bayesian network (DBN) is often called a "two-timeslice" BN (2TBN) because it says that at any point in time T, the value of a variable can be calculated from the internal regressors and the immediate prior value (time T-1). DBNs were developed by Paul Dagum in the early 1990s at Stanford University's Section on Medical Informatics. [1] [2] Dagum developed DBNs to unify and extend traditional linear state-space models such as Kalman filters, linear and normal forecasting models such as ARMA and simple dependency models such as hidden Markov models into a general probabilistic representation and inference mechanism for arbitrary nonlinear and non-normal time-dependent domains. [3] [4]

Today, DBNs are common in robotics, and have shown potential for a wide range of data mining applications. For example, they have been used in speech recognition, digital forensics, protein sequencing, and bioinformatics. DBN is a generalization of hidden Markov models and Kalman filters. [5]

DBNs are conceptually related to probabilistic Boolean networks [6] and can, similarly, be used to model dynamical systems at steady-state.

See also

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References

  1. Paul Dagum; Adam Galper; Eric Horvitz (1992). "Dynamic Network Models for Forecasting" (PDF). Proceedings of the Eighth Conference on Uncertainty in Artificial Intelligence. AUAI Press: 41–48.
  2. Paul Dagum; Adam Galper; Eric Horvitz; Adam Seiver (1995). "Uncertain Reasoning and Forecasting". International Journal of Forecasting. 11 (1): 73–87. doi: 10.1016/0169-2070(94)02009-e .
  3. Paul Dagum; Adam Galper; Eric Horvitz (June 1991). "Temporal Probabilistic Reasoning: Dynamic Network Models for Forecasting" (PDF). Knowledge Systems Laboratory. Section on Medical Informatics, Stanford University.
  4. Paul Dagum; Adam Galper; Eric Horvitz (1993). "Forecasting Sleep Apnea with Dynamic Network Models". Proceedings of the Ninth Conference on Uncertainty in Artificial Intelligence. AUAI Press: 64–71.
  5. Stuart Russell; Peter Norvig (2010). Artificial Intelligence: A Modern Approach (PDF) (Third ed.). Prentice Hall. p. 566. ISBN   978-0136042594. Archived from the original (PDF) on 20 October 2014. Retrieved 22 October 2014. dynamic Bayesian networks (which include hidden Markov models and Kalman filters as special cases)
  6. Harri Lähdesmäki; Sampsa Hautaniemi; Ilya Shmulevich; Olli Yli-Harja (2006). "Relationships between probabilistic Boolean networks and dynamic Bayesian networks as models of gene regulatory networks". Signal Processing. 86 (4): 814–834. doi:10.1016/j.sigpro.2005.06.008. PMC   1847796 . PMID   17415411.

Further reading


Software