My point was that forecasting can be done either in linear fashion (regression, for example), or non-linear fashion (genetic algorthims, neural nets).
The question did not address the specifics of what exactly "short-term" means. Are we talking point to point? Is it ticks (no time element), minutes, hours, days?
I claim no expertise, but the research I've been made aware of seems to point to non-linear methods have better success forecasting price movement in the financial markets. I have yet to be convinced of that in a meaningful fashion, by the way, but neither am I convinced that linear methods do particularly well either.
