Tea is known to contain high concentrations of fluoride; tea consumption, therefore, can contribute significantly to total fluoride intake. Recently, green tea has been studied for its fluoride content and for improving its brewing conditions.
1 The effect of carbon treatment on fluoride levels in various kinds of teas and fruit and vegetable juices has been examined.
2 King, and Tsang
3 determined the fluoride content of Chinese teas available in Hong Kong. The fluoride content in tea and soil from tea plantations has been assayed using a fluoride ion selective electrode.
There are two contrasting viewpoints concerning the explanation of observed fluctuations in economic and financial markets. According to the first {Newclassical) view the main source of fluctuations is to be found in exogenous, random shocks to fundamentals. In the absence of shocks, prices and other variables would converge to a steady state (growth) path, completely determined by fundamentals. According to the second [Keynesian) view a significant part of observed fluctuations is caused by nonlinear economic laws. Even in the absence of any external shocks, nonlinear market laws can generate endogenous business fluctuations. The newclassical view is intimately related to the concept of rational expectations, whereas animal spirits or market psychology have been an important Keynesian theme.
In finance the two different viewpoints lead to opposite views concerning the efficiency of financial markets. In the efficient market hypothesis (EMH) the current price already contains all information and past prices can not help in predicting future prices. Parametric stochastic processes have been used in the empirical literature that are consistent with the EMH. Examples include random walk processes, GARCH-processes and the like. In contrast, Keynes already argued that stock prices are not only determined by fundamentals, but in addition market psychology and investors animal spirits influence financial markets significantly. In the Keynesian view, simple technical trading rules, such as extrapolation of a trend, may help predict future price changes. In fact, recently Brock, Lakonishok and LeBaron (1992) have indeed shown that simple technical trading rules, such as moving average and trading range break, when used in predicting the Dow Jones Index, consistently outperform several popular stochastic finance models, such as the random walk and the GARCH-model.
Open international capital markets have been instrumental in efficiently allocating risk and allowing firms to fulfill their capital investment demand. Also, systematic and credit risk measures may affect business investment through multiple channels. First, changes in market interest rates imply changes in the cost of capital, which in turn affect investment; the so-called interest channel. Second, changes in market interest rates affect the net cash flow available to a firm.
