The Jarque-Bera normality test verifies if the residues of the regression hyper-plane are normal random variables.In this paper we present some numerical and Monte Carlo methods to obtain normal residues if the Jarque-Bera test fails. We consider the case when we know the pdf, the cdf and the...

In this paper we will test the homoscedasticity of errors using the Goldfeld-Quandt test and we will classify the points using the explanatory variable by which we sort them. We will also use the Hartley test for the equality of the class error variances (if we have at least two classes). For...

In this paper we will classify patterns using a modified Perceptron algorithm (Dumitrache et al., 1999). The generalization uses the eigenvalues and the eigenvectors of the sample covariance matrix, as we did for classifying patterns using PCR (Ciuiu 2007b).We shall also define measurements for...

use such copula to model the dependence between two random variables that cannot be both lower than given values, but each can be lower than the corresponding value. This can be used in the Phillips curve. Even we consider the values of inflation and unemployment ent or their rates, there exist...