The definition of time is still an open question when one deals with high frequency time series. If time is simply the calendar time, prices can be modeled as continuous random processes and values resulting from transactions or given quotes are discrete samples of this underlying dynamics. On the contrary, if one takes the business time point of view, price dynamics is a discrete random proces...

This paper describes the Banco de la República’s FX intervention policy, with a focus on its objectives and main features. It then argues, based on a review of the literature on the effectiveness of sterilized intervention in Colombia, that this tool is not a useful way of coping with the challenges posed by medium-term external factors such as quantitative easing in advanced economies, reduced...

We discuss price variations distributions in foreign exchange markets, characterizing them both in calendar and business time frameworks. The price dynamics is found to be the result of two distinct processes, a multi-variance diffusion and an error process. The presence of the latter, which dominates at short time scales, leads to indeterminacy principle in finance. Furthermore, dynamics does ...

We investigate intra-day foreign exchange (FX) time series using the inverse statistic analysis developed in [1,2]. Specifically, we study the time-averaged distributions of waiting times needed to obtain a certain increase (decrease) ρ in the price of an investment. The analysis is performed for the Deutsch Mark (DM) against the $US for the full year of 1998, but similar results are obtained f...

The foreign currency exchange market is the highest and most liquid of the financial markets, with an estimated $1 trillion traded every day. Foreign exchange rates are the most important economic indices in the international financial markets. The prediction of them poses many theoretical and experimental challenges. This paper reports empirical proof that a neural network model is applicable ...

(2013) Forecasting foreign exchange rates with adaptive neural networks using radial basis functions and particle swarm optimization. The content must not be changed in any way or reproduced in any format or medium without the formal permission of the copyright holder(s) Forecasting foreign exchange rates with adaptive neural networks using radial-basis functions and particle swarm optimization...

Four foreign exchange spot rate series, recorded on an hourly basis for a six-month period in 1986 are examined. A seasonal GARCH model is developed to describe the time-dependent volatility apparent in the percentage nominal return of each currency. Hourly patterns in volatility are found to be remarkably similar across currencies and appear to be related to the opening and closing of the worl...