Title :
Tradeoffs in knowledge-based construction of probabilistic models
Author :
Provan, Gregory M.
Author_Institution :
Dept. of Comput. & Inf. Sci., Pennsylvania Univ., Philadelphia, PA, USA
fDate :
11/1/1994 12:00:00 AM
Abstract :
In many domains, the ability to use a knowledge base to automatically construct alternative probabilistic network models and then compare them is desirable. This paper makes two novel contributions towards achieving that goal: first, it analyzes a parameterized class of (a) static, and (b) temporal influence diagram, models which differ in the time-series process describing the temporal evolution of the system being modeled. Second, it applies general scoring metrics for comparing these models with respect to predictive accuracy and computational efficiency. The network rankings facilitate comparing the accuracy/efficiency tradeoffs entailed in using TIDs which differ in (1) the accuracy of capturing the temporal evolution of a dynamic system and (2) data and computational requirements. The scoring metrics are used to compare networks in which all variables evolve according to a Markov process with two novel domain-dependent network approximations. These approximations model the evolution of a parsimonious subset of variables rather than all variables
Keywords :
Markov processes; digital simulation; graph theory; knowledge based systems; probability; time series; Markov process; accuracy/efficiency tradeoffs; computational efficiency; domain-dependent network approximations; general scoring metrics; knowledge-based construction; network rankings; parsimonious subset; predictive accuracy; probabilistic network models; static models; temporal evolution; temporal influence diagram models; time-series process; Accuracy; Bayesian methods; Computer networks; Costs; Information science; Intelligent networks; Knowledge based systems; Markov processes; Predictive models; Time series analysis;
Journal_Title :
Systems, Man and Cybernetics, IEEE Transactions on