The use of Support Vector Machines (SVMs) is studied in financial forecasti
ng by comparing it with a multi-layer perceptron trained by the Back Propag
ation (BP) algorithm. SVMs forecast better than BP based on the criteria of
Normalised Mean Square Error (NMSE). Mean Absolute Error (MAE), Directiona
l Symmetry (DS) Correct Up (CP) trend and Correct Down (CD) trend S&P 500 d
aily price index is used as the data set. Since there is no structured way
to choose the free parameters of SVMs, the generalisation error with respec
t to the free parameters of SVMs is investigated in this experiment. As ill
ustrated in the experiment, they have little impact on the solution. Analys
is of the experimental results demonstrates that it is advantageous to appl
y SVMs to forecast the financial rime series.