Challenges to sustaining the productivity of oceanic and coastal fisheries
have become more critical and complex as these fisheries reach the upper
limits to ocean harvests. In addition, it is now clear that we are managing
interactive and dynamic food webs rather than sets of independent single-species
The late Neogene (the period between − 14 and − 2.4 Ma) is one of the most
interesting phases in understand the present conWguration of terrestrial
ecosystems. It was during this time that the change took place from the
middle Miocene dominant subtropical forests that stretched across southern
Europe and western Asia to a more open but still wooded biotope that
now prevails in warm–temperate areas. This change in vegetation, which
strongly aVected the composition of mammalian faunas, seems to be linked
to the rapid spread of grasses around 8–10 Ma ago....
There have been some attempts to explain theoretically the behavior of the stock return volatility.
Veronesi (1999) constructs a model with regime shifts in the endowments in which investors will-
ingness to hedge against their own uncertainty on the true regime generates overreaction to good
news in bad times and volatility clustering. In contrast to that paper, I assume that the exogenous
state variables are not subject to regimes, neither do they exhibit mean-reversion.
Moreover, the necessity of taking into account monetary policy in the
rational expectations framework has been demonstrated in particular by the
seminal work of Mankiw and Miron (1986) for the short end of the term
structure. For the long part of the term structure, Fuhrer (1996), without
specifying any process for the perception of regime shifts by agents, has shown
that the expectations hypothesis can be accepted for the long part of the yield
curve if we allow some small and discrete changes in the coe¢ cients of the
reaction function for the Federal Reserve System.
This book summarizes likely challenges to U.S. interests in the Persian Gulf, identifies key uncertainties and trends, and assesses the implications of those trends for the United States. The authors examine shifting military balances and weaknesses, the threat from weapons of mass destruction (WMD); social and economic trends in the region; potential regime changes; and the effects of the U.S. military presence in the region.
The operational procedures of the Bank of Greece underwent major changes during the 1990s. These shifts in operational strategy made interest rates the main tool of monetary policy for the first time in Greece. This paper examines the effects of changes in the bank’s operational interest rates on market interest rates at eight maturities and for different operational regimes. A major feature of our study is the application of the event study methodology used in finance, which has not been employed in any previous study on this subject.
More generally, private participation can successfully improve access to
infrastructure services (telecommunication, energy, transport, water), where workable
competition can be introduced, for example in many telecommunication systems. In non-
competitive markets, case by case decisions are required to assess whether public or
private provision may be preferable depending, in particular, on whether more risks for
commercial performance can be shifted effectively to the private sector.