38 research outputs found
Evaluation of the Performance of the Markov Blanket Bayesian Classifier Algorithm
The Markov Blanket Bayesian Classifier is a recently-proposed algorithm for
construction of probabilistic classifiers. This paper presents an empirical
comparison of the MBBC algorithm with three other Bayesian classifiers: Naive
Bayes, Tree-Augmented Naive Bayes and a general Bayesian network. All of these
are implemented using the K2 framework of Cooper and Herskovits. The
classifiers are compared in terms of their performance (using simple accuracy
measures and ROC curves) and speed, on a range of standard benchmark data sets.
It is concluded that MBBC is competitive in terms of speed and accuracy with
the other algorithms considered.Comment: 9 pages: Technical Report No. NUIG-IT-011002, Department of
Information Technology, National University of Ireland, Galway (2002
Automatically combining static malware detection techniques
Malware detection techniques come in many different flavors, and cover different effectiveness and efficiency trade-offs. This paper evaluates a number of machine learning techniques to combine multiple static Android malware detection techniques using automatically constructed decision trees. We identify the best methods to construct the trees. We demonstrate that those trees classify sample apps better and faster than individual techniques alone
Response mapping methods to estimate the EQ-5D-5L from the Western Ontario McMaster Universities Osteoarthritis in patients with hip or knee osteoarthritis
Objectives: The mapping technique can estimate generic preference-based measure scores through a specific measure that cannot be used in economic evaluations. This study compared 2 response mapping methods to estimate EQ-5D-5L scores using the Western Ontario McMaster Universities Osteoarthritis (WOMAC). Methods: The sample consisted of 758 patients with the hip or knee osteoarthritis recruited in baseline. Bayesian networks (BN) and multinomial logistic regression (ML) were used as response mapping models. Predictions were obtained using the 6-month follow-up as a validation sample. The mean absolute error, mean squared error, deviation from the root mean squared error and intraclass correlation coefficient were calculated as precision measures. Results: There was 5.5% of missing data, which was removed. The mean age was 69.6 years (standard deviation = 10.5), with 61.6% of women. The BN model presented lower mean absolute error, mean squared error, root mean squared error and higher intraclass correlation coefficient than the ML model. Only the WOMAC items pain and physical function items were related with the EQ-5D-5L dimensions. Conclusion: BN response mapping models are more robust methods, with better prediction results, than ML models. The BN model also provided a graphic representation of the dependency relationships between the EQ-5D-5L dimensions and the different WOMAC items that could be useful in the clinical investigation of patients with hip or knee osteoarthritis
Hacia la sostenibilidad portuaria mediante modelos probabilísticos: redes bayesianas
It is necessary that a manager of an infrastructure knows relations between variables. Using Bayesian networks, variables can be classified, predicted and diagnosed, being able to estimate posterior probability of the unknown ones based on known ones. The proposed methodology has generated a database with port variables, which have been classified as economic, social, environmental and institutional, as addressed in of smart ports studies made in all Spanish Port System. Network has been developed using an acyclic directed graph, which have let us know relationships in terms of parents and sons. In probabilistic terms, it can be concluded from the constructed network that the most decisive variables for port sustainability are those that are part of the institutional dimension.
It has been concluded that Bayesian networks allow modeling uncertainty probabilistically even when the number of variables is high as it occurs in port planning and exploitation.En la explotación y gestión es necesario que el gestor de la infraestructura conozca las relaciones entre las variables en juego, lo cual es factible con el uso de redes bayesianas que permiten clasificar, predecir y diagnosticar las variables, pudiendo incluso estimar la probabilidad posterior de las no conocidas en base a las conocidas. En la metodología propuesta se ha generado una base de datos con variables portuarias, clasificadas en económicas, sociales, ambientales e institucionales, tal como se abordan los estudios de smart ports, en el Sistema Portuario Español, desarrollando una red mediante un grafo dirigido acíclico para conocer las relaciones en términos de padres e hijos. En términos probabilísticos, se observa que las variables más decisoras para la sostenibilidad portuaria son las institucionales.
Se concluye que las redes bayesianas permiten modelar la incertidumbre de forma probabilística incluso cuando el número de variables es elevado como en la planificación y explotación portuaria