To me a newbie, a position length of 30 minutes can be evaluated as a relatively small timeframe based on comparatively high frequency data (which does Not necessarily generate a larger number of trades, I would guess).
http://www.elitetrader.com/vb/showthread.php?s=&threadid=36170&perpage=6&pagenumber=2
http://www.elitetrader.com/vb/showthread.php?s=&threadid=36170&perpage=6&pagenumber=2
Quote from prophet:
My 6E systems are almost always in the market, trading 2 to 5 times per 24 hour period with position lengths of 30 minutes to 10 hours. The systems don't avoid economic number releases, so I do see occasional +/- 100 pip days. Average daily return is about 25 pips/day, with an intraday PnL loss stop set at 120 pips.