Advances in Decision Sciences
Volume 2009 (2009), Article ID 125308, 22 pages
doi:10.1155/2009/125308

Modified neural network algorithms for predicting trading signals of stock market indices

C.D. Tilakaratne1 , M.A. Mammadov2 and S.A. Morris2

1Department of Statistics, University of Colombo, P.O. Box 1490, Colombo 3, Sri Lanka
2Graduate School of Information Technology and Mathematical Sciences, University of Ballarat, P.O. Box 663, Ballarat, Victoria 3353, Australia

Abstract

The aim of this paper is to present modified neural network algorithms to predict whether it is best to buy, hold, or sell shares (trading signals) of stock market indices. Most commonly used classification techniques are not successful in predicting trading signals when the distribution of the actual trading signals, among these three classes, is imbalanced. The modified network algorithms are based on the structure of feedforward neural networks and a modified Ordinary Least Squares (OLSs) error function. An adjustment relating to the contribution from the historical data used for training the networks and penalisation of incorrectly classified trading signals were accounted for, when modifying the OLS function. A global optimization algorithm was employed to train these networks. These algorithms were employed to predict the trading signals of the Australian All Ordinary Index. The algorithms with the modified error functions introduced by this study produced better predictions.