Interactions between interest rates and the transmission of monetary and economic news: the cases of US and UK.

In recent years, economies have become more and more interdependent. The constitution of commercial and monetary unions has increased the level of coordination of public decisions. On the other hand, some countries still have an strong influence at the world or regional levels. This paper studies the evolutions of UK and USA interest rates markets as well as their interactions during the last decade. Thus, we determine empirically the main determinants of interest rates in both countries using several explanatory variables among which, macroeconomic, monetary and financial variables. In particular, it is of interest to determine whether interest rates react and how to the publication of key economic and financial figures. We thus considered in this paper the effects of news, as measured by the difference between anticipated and observed data, on the interest rates means and volatilities. Determining the interest rates dynamics from their national determinants also allow us to evaluate the degrees of transparency and credibility of central banks in both countries. Second, we are interested in measuring the degree of integration of American and British economies by analyzing the spillover and feedback effects between interest rates as well as news spillover effects. In order to take into account the evolutions of interest rates values as well as their volatilities, we use a VAR model where the error term is specified as a multivariate GARCH. Contrary to previous papers in the same area, we do not assume that there is a "small" and a "big" country as we allow any causality to be determined by the data. We find that factors that account for most variations in interest rates are, for both countries, the monetary policy decisions, the price levels and the rate of unemployment. Moreover, the reaction of UK interest rates to US variables tend to be less important in recent years, while we observe the contrary the other way round. Those seemingly contradictory results can gain sense if one takes into account the emergence of EMU as a new economic power.