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Stochastic Markets

The previous results were derived assuming i.i.d. markets, but can be extended to time-dependent markets. In stochastic markets, it has been shown, with increasing levels of generality on the stochastic process, that

\begin{displaymath}\lim_{n \rightarrow \infty} \frac{1}{n} \ln \frac{S_n}{S_n^*} \leq 0,
\end{displaymath} (12)

for every sequential portfolio. This tells us that b*(F) is asymptotically optimal in this sense, and W*(F) is the highest possible exponent for the growth rate of wealth.

Magnus Bjornsson
1998-05-12