Uncertainty about future inflation is often claimed to be one of the most important costs of inflation, since it distorts the workings of the price system and leads to allocational inefficiencies. This paper analyses U.K. inflation between 1950 and 1994 using the ARCH methodology, which enables...

Many high frequency economic or financial time series display two empirical characteristics: high kurtosis and positive autocorrelation in the centred and squared observations. The first-order autocorrelation is typically low, and the autocorrelation function decays slowly. These series are...

Because durable goods have the quality of an asset, risk-averse consumers want to pay a lower price for durable than for nondurable goods so that they are compensated for the risk of price changes; they require risk premium. Since the exchange rate is a strong source of uncertainty in import...

This paper considers the moments of a family of first-order GARCH processes. First, a general condition of the existence of any integer moment of the absolute values of the observations is given. Second, a general expression for this moment as a function of lower-order moments is derived. Third,...

The book deals with the econometric analysis of high frequency financial time series. It emphasizes a new nonparametric approach to volatility models and provides theoretical and empirical comparisons with conventional ARCH models, applied to foreign exchange rates. Nonparametric models are...

In the framework of the Engle-type (G)ARCH models, I demonstrate that there is a family of symmetric and asymmetric density functions for which the asymptotic efficiency of the semiparametric estimator is equal to the asymptotic efficiency of the maximum likelihood estimator. This family of...