<P>Empirical and theoretical evidence of economic chaos</P>
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<P>A Random Walk or Color Chaos<BR>on the Stock Market?<BR>Time-Frequency Analysis of S&P Indexes</P>
<P> <BR>Trends, Shocks, Persistent Cycles in Evolving<BR>Economy - Business Cycle Measurement in Time-Frequency<BR>Representation</P>
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