Do Spanish Stock Market Prices Follow a Random Walk?

In this article we test the random walk hypothesis in the Spanish daily stock market prices by means of using fractionally integrated techniques. We use a version of the tests of Robinson (1994) that permit us to test I(d) statistical models. The results show that though fractional degrees of integration are plausible in some cases, the confidence intervals are generally narrow, including the unit root in all cases. Therefore, there is very little evidence of fractional integration, despite the length of the series, implying that the standard practice of taking first differences when modelling stock prices is adequate. In addition, the tests cannot reject that the underlying I(0) disturbances are white noise, supporting thus the (weakly) efficient market hypothesis in the Spanish stock market.Stock market; Unit roots; Long memory; Market efficiency

Testing of Nonstationary Cycles in Financial Time Series Data

In this article we propose a new method for testing nonstationary cycles in financial time series data. In particular, we use a procedure due to Robinson (1994) that permits us to test unit root cycles in raw time series. These tests have several distinguishing features compared with other procedures. In particular, they have a standard null limit distribution and they are the most efficient ones when directed against the appropriate alternatives. In addition, the procedure of Robinson (1994) allows us to test unit root cycles at each of the frequencies, and thus permits us to approximate the number of periods per cycle. The results, based on the daily structure of the Spanish stock market prices (IBEX 35) show that some intra-year cycles occur, and they take place at approximately 6, 9 or between 24 and 50 periods.Stock market; Unit root cycles; Nonstationarity

How the epidemiological transition affects health policy isues in three Latin American countries

The authors focus on health policy issues associated with health reform needed to meet the health needs arising from the demographic and epidemiological transitions. They illustrate these policy issues by analyzing Brazil, Colombia, and Mexico, whose populations represent about 60 percent of Latin America's population. Brazil, Colombia, and Mexico are facing an important decline in mortality and fertility rates. New health problems have arisen related to rapid urbanization and industrialization - for example, injuries, accidental intoxication and poisoning, and the occupational and noncommunicable conditions (such as hypertension and diabetes) affecting an aging population. At the same time, these countries are not free of old health problems - such as infectious and parasitic diseases - although their mortality rates are declining. That is, old and new health problems coexist while wide social disparities persist in these developing Latin American countries. The epidemiological diversity and the speed of change in disease profiles makes the health transition in many developing countries more complex than the situation developed countries faced. Most of these countries also have inadequate health infrastructure and are unlikely to be able to afford to develop them in the next decade or so. Most governments are also being pressed to adopt the therapeutic medical model to deal with noncommunicable conditions. The authors arrive at the following seven conclusions about the implications of the epidemiological transition for health policy in developing Latin American countries. The transition offers an empirical framework for strategic planning for the health system, allowing policymakers to anticipate future trends and causes of mortality and anticipate disease scenarios. Since more disease is expected among the adult and elderly populations, the health system's mission should be revised with more emphasis on disease prevention and control and less on satisfying demand. Existing inequities in the geographical distribution of health resources and in the quality of care between health institutions should be corrected to avoid greater epidemiological polarization. The health care model should be reformed to strengthen the technical capacity to provide preventive and curative services at the first level of care to control the dual burden of disease. Efficiency and quality of care need to be substantially improved to accommodate the greater demand for clinical services, especially those provided at hospitals. Criteria for setting priorities in the health sector must be defined, so resources can be allocated among competing health needs and socioeconomic groups. These countries need to strengthen their ability to analyze the health status of populations, to evaluate the health system's performance, and to design cost-effective interventions to deal with noncommunicable diseases.Health Monitoring&Evaluation,Health Systems Development&Reform,Housing&Human Habitats,Agricultural Knowledge&Information Systems,Gender and Health

A New Form of Path Integral for the Coherent States Representation and its Semiclassical Limit

The overcompleteness of the coherent states basis leads to a multiplicity of representations of Feynman's path integral. These different representations, although equivalent quantum mechanically, lead to different semiclassical limits. Two such semiclassical formulas were derived in \cite{Bar01} for the two corresponding path integral forms suggested by Klauder and Skagerstan in \cite{Klau85}. Each of these formulas involve trajectories governed by a different classical representation of the Hamiltonian operator: the P representation in one case and the Q representation in other. In this paper we construct a third representation of the path integral whose semiclassical limit involves directly the Weyl representation of the Hamiltonian operator, i.e., the classical Hamiltonian itself.Comment: 16 pages, no figure