This paper reconsiders whether monetary policy in small open economies responds to exchange rates by studying possible parameter instabilities in a Dynamic Stochastic General Equilibrium model. The main focus of the paper is to revisit preceding evidence on the response to exchange rate movements by the Bank of England and determine if its reaction function has remained constant throughout the sample. To this end, I estimate a small open economy general equilibrium model using Bayesian econometric techniques over rolling windows. I find overwhelming evidence of shifts in several parameters, including those related to the policy rule. Furthermore, posterior odds tests reveal a time-varying response to exchange-rate fluctuations by the monetary authorities. The results favor the model with the nominal exchange rate embedded in the policy rule for the initial subsamples. However, the evidence steadily evolves across windows and ultimately changes to prefer the model specification with no exchange rate. The paper also documents evident variations in the model dynamics derived from the instability of parameters via rolling-window impulse response functions and variance decomposition analysis.
We provide an alternative perspective on the benefits of investing in Multinational Companies (MNCs) using a unique hand-collected dataset on the location of UK firm's sales and subsidiaries from 1998 to 2015. We find that investors can gain diversification benefits from investing in MNCs, but not necessarily firms with the greatest global reach. We also show that firm's returns tend not to be influenced by the geographical regions where they report sales and subsidiaries. The results suggest a new category of firms that may be beneficial for diversification - firms that are significantly influenced by the stock markets of a geographical region but do not report sales or subsidiaries in that region. This implies that investors should analyse the geographical regions that influence firm returns rather than the location of their sales and subsidiaries. Intuitively, these should be the same, but our results show a difference between the geographical location of a firm's sales and subsidiaries, and the regions that influence the firm returns. We recommend that investors look beyond the location of MNC activities and investigate the geographical regions that influence firms' returns when creating portfolios.