Second, we focus primarily on exchange rate conditional means as opposed to conditional
variances. That is, we focus primarily on the determination of exchange rates themselves, as opposed to
their volatility. We maintain this focus both because the conditional mean is of intrinsic interest, and
because high-frequency discrete-time volatility cannot be extracted accurately unless the conditional
mean is modeled adequately. Hence our work differs in important respects from that of Andersen and
Bollerslev (1998), Bollerslev, Cai and Song (2000), Ederington and Lee (1993), and Payne (1996), for
example, who examine calendar and news effects in high-frequency asset return volatility but do not
consider the effects of news on returns themselves.