Revisiting Uncovered Interest Rate Parity: Switching Between UIP and the Random Walk

In this paper, we examine in which periods uncovered interest rate parity was likely to hold. Empirical research has shown mixed evidence on UIP. The main finding is that it doesn’t hold, although some researchers were not able to reject UIP in periods with large interest differentials or high volatility. In this paper, we introduce a switching regime framework in which we assume that the exchange rate can switch between a UIP regime and a random walk regime. Our empirical results provide evidence that exchange rate movements were consistent with UIP over some periods, but not all. Consistent with the existing literature we also show that in periods with large interest differentials or increased exchange rate volatility, the exchange rate is more likely to follow UIP.Exchange rate dynamics;Uncovered interest rate parity;Markov regime switching

A Range-Based Multivariate Model for Exchange Rate Volatility

In this paper we present a parsimonious multivariate model forexchange rate volatilities based on logarithmic high-low ranges ofdaily exchange rates. The multivariate stochastic volatility modeldivides the log range of each exchange rate into two independentlatent factors, which are interpreted as the underlying currencyspecific components. Due to the normality of logarithmic volatilitiesthe model can be estimated conveniently with standard Kalman filtertechniques. Our results show that our model fits the exchange ratedata quite well. Exchange rate news seems to be very currency-specificand allows us to identify which currency contributes most to bothexchange rate levels and exchange rate volatilities.exchange rates;multivariate stochastic volatility models;range-based volatility

Regime Jumps in Electricity Prices

Electricity prices are known to be very volatile and subject to frequent jumps due to system breakdown, demand shocks, and inelastic supply. As many international electricity markets are in some state of deregulation, more and more participants in these markets are exposed to these stylised facts. Appropriate pricing, portfolio, and risk management models should incorporate these facts. Authors have introduced stochastic jump processes to deal with the jumps, but we argue and show that this specification might lead to problems with identifying the true mean-reversion within the process. Instead, we propose using a regime jump model that disentangles mean-reversion from jump behaviour. This model resembles more closely the true price path of electricity prices.stochastic models;electricity prices;international energy markets;jumps;mean reversion

Hedging Exposure to Electricity Price Risk in a Value at Risk Framework

This paper deals with the question how an electricity end-consumer or distribution company should structure its portfolio with energy forward contracts. This paper introduces a one period framework to determine optimal positions in peak and off-peak contracts in order to purchase future consumption volume. In this framework, the end-consumer or distribution company is assumed to minimize expected costs of purchasing respecting an ex-ante risk limit defined in terms of Value at Risk. Based on prices from the German EEX market, it is shown that a risk-loving agent is able to obtain lower expected costs than for a risk-averse agent.Electricity prices;Forward risk premium;Hedge ratios;Mean variance