Machine Learning and Heuristics III (MLHIII)

CHAIR: ARMANDO VIEIRA

Time: Monday 21st March, 16h30-18h10

Paper ID   Title
   
MLHIII-1 Efficiency Aspects of Neural Network Architecture Evolution Using Direct and Indirect Encoding
MLHIII-2 Genetic Algorithm Optimization of an Artificial Neural Network for Financial Applications
MLHIII-3 A Method to Improve Generalization of Neural Networks: Application to the Problem of Bankruptcy Prediction
MLHIII-4 An Adaptive Neural System for Financial Time Series Tracking
MLHIII-5 Probabilistic Artificial Neural Networks for Malignant Melanoma Prognosis


MLHIII-1
 
Title: Efficiency Aspects of Neural Network Architecture Evolution Using Direct and Indirect Encoding
Author(s): H. Kawasnicka,
M. Paradowski
Abstract: sing a GA as a NN designing tool deals with many aspects. We must decide, among others, about: coding schema, evaluation function, genetic operators, genetic parameters, etc. This paper focuses on an efficiency of NN architecture evolution. We use two main approaches for neural network representation in the form of chromosomes: direct and indirect encoding. Presented research is a part of our wider study of this problem. We present the influence of coding schemata on the possibilities of evolving optimal neural network.


MLHIII-2
 
Title: Genetic Algorithm Optimization of an Artificial Neural Network for Financial Applications
Author(s): Serge Hayward
Abstract: Model discovery and performance surface optimization with genetic algorithm demonstrate profitability improvement with an inconclusive effect on statistical criteria. The examination of relationships between statistics used for economic forecasts evaluation and profitability of investment decisions reveals that only the ‘degree of improvement over efficient prediction’ shows robust links with profitability. If profits are not observable, this measure is proposed as an evaluation criterion for an economic prediction. Also combined with directional accuracy, it could be used in an estimation technique for economic behavior, as an alternative to conventional least squares.


MLHIII-3
 
Title: A Method to Improve Generalization of Neural Networks: Application to the Problem of Bankruptcy Prediction
Author(s): Armando Vieira ,
João C. Neves ,
Bernardete Ribeiro
Abstract: The Hidden Layer Learning Vector Quantization is used to correct the predictions of multilayer perceptrons for classification of high-dimensional data. Corrections are significant for problems with insufficient training data to constrain learning. Our method allows the conclusion of a large number of attributes without compromising the generalization capabilities of the network. The method is applied to the problem of bankruptcy prediction with excellent results


MLHIII-4
 
Title: An Adaptive Neural System for Financial Time Series Tracking
Author(s): A. Dantas,
J.Seixas
Abstract: In this paper, we present a neural network based system to generate an adaptive model for financial time series tracking. This kind of data is quite relevant for data quality monitoring in large databases. The proposed system uses the past samples of the series to indicate its future trend and to generate a corridor inside which the future samples should lie. This corridor is derived from an adaptive forecasting model, which makes use of the walk-forward method to take into account the most recent observations of the series and bring up to date the values of the neural model parameters. The model can serve also to manage other time series characteristics, such as the detection of irregularities.


MLHIII-5
 
Title: Probabilistic Artificial Neural Networks for Malignant Melanoma Prognosis
Author(s): R. Joshi,
C. Reeves,
C. Johnston
Abstract: Artificial Neural networks (ANNs) have found pplications in a wide variety of medical problems and have proved successful for non-linear regression and classification. This paper details a novel and flexible probabilistic non-linear ANN model for the prediction of conditional survival probability of malignant melanoma patients. Hazard and probability density functions are also estimated. The model is trained using the log-likelihood function, and generalisation has been addressed. Unrestricted by assumptions that are unrealistic or parametric forms that are difficult to justify, the model thereby attains advantage over traditional statistical models. Furthermore, an estimate of the variance-covariance matrix is obtained using the asymptotic Fisher information matrix. Implemented in an Excel spreadsheet, the model’s user-friendly design further adds to its flexibility, with much potential for use by statisticians as well as researchers.