Hello All,
The Hurst Exponent can be calculated for a time series as a value for 0 to 1. A value of 0.5 says the time series is a random walk, < 0.5 that it is mean-reverting, and > 0.5 that it is trending. I've over-simplified a bit so see these references:
'Rescaled Range Analysis: A Method for Detecting Persistence, Randomness, or Mean Reversion in Financial Markets' http://blogs.cfainstitute.org/investor/2013/01/30/rescaled-range-analysis-a-method-for-detecting-persistence-randomness-or-mean-reversion-in-financial-markets/
'Some comments on Hurst exponent and the long memory processes on
capital markets' http://www.ual.es/~jgarcia/index_archivos/HURST.pdf
I've copied some code from the PyEEG project http://code.google.com/p/pyeeg/ but initially I am getting Hurst Exponent values for SPY and for individual stocks that are around 0.7. In both references above the S&P 500 has a calculated Hurst Exponent of 0.49 - 0.5.
What am I doing wrong? And is there a trading method here?
Regards,
Peter