El modelo gaussiano GARCH(1,1) ha sido empleado, tradicionalmente, en el estudio de la tasa de cambio; sin embargo, un número importante de estudios recientes (utilizando modelos FIGARCH e HYGARCH) ha encontrado evidencia de persistencia en su volatilidad. En este trabajo, usando una estrategia...

Castaño et al. (2008) proposed a test to investigate the existence of long memory based on the fractional differencing parameter of an ARFIMA (p, d, q) model. They showed that using an autoregressive approximation with order equal to the nearest integer of p* = T1/3 for the short-term component...

This paper asks whether the ‘leverage effect’ –as defined by Black (1976) for stock markets– is also a characteristic of foreign exchange markets. The study focuses on five Latin American emerging markets which have adopted a floating exchange regime. It

In regression analysis, it is frequently required to transform the dependent variable in order to obtain additivity and normal errors with constant variance. Box and Cox (1964) proposed a parametric power transformation based on the assumption of normality with the aim to achieve these goals....

In this work, we present a modification of the hypothesis testing procedure for the existence of long memory in the stationary and invertible ARFIMA(p,d,q) process proposed by Castaño, Gómez and Gallón (2008). This modification allows assessing the existence of a fractional root in a...

The objective of this article is to explain the decreasing trend of monthly consumption per user in Medellín during the period 1985•1991. To reach the goal it was necessary to search in economic theory for those methodological tools allowing an appropiate analysis of the problem posed....

This paper analyses the impact of various pricing systems for electricity in Medellín, Colombia. The basic system is one of simple marginal cost pricing with no two-part elements and single price is that for which Medellín can buy and sell electricity form national network. We consider various...

Many of the time series used in practice are monthly observations and due to the fact that the number of times any weekday occurs, depends on the month in question, the series can be influenced by changes in the number of working days. Some of these series can also be influenced by other...

This paper tries to test an economic explanation of the industrial demand for electricity in Colombia during the period 1970-1983. The estimation of the translog equations shows the complementary or substitutability between energy and other inputs in the industrial production function. After...

This article shows a general overview of the technological structure found in the industrial sector in Antioquia during the period 1975-1987. The analysis assumes a two-level production function. In the first level the inputs used are capital, employment, energy and other raw material. The...