Quote from nitro:
peartrader,
All this stuff and your previous post is "arithmetic" to a professional pair trader, i.e., it is elementary.
I realize that this is elementary...I realize that not everyone is a 'professional' trader...I also realize that this has worked for me for quite some time.
I don't have all the answers...if anyone here does, please speak up! I was simply tying to offer some thoughts to those who are looking for answers.
You are right...cutting losses systematically is 'elementary' ...but why then are so many of the post here about people losing money and blowing up?
Because their system changed?? Because the market changed?? Possibly. Understandable too....markets are dynamic, and the industry is dynamic. One of the hardest lessons to learn about trading a pair is that you can't trade it like a stock...meaning that the chart of a pair can't be read like a single-stock chart.
Some argue that pair trading ONLY works in side-ways markets...that is true ONLY if your system tries to identify support and resistance between an oscillating ratio. This could be why many systems have lost money....because in the past 9 weeks, we have had a bit of a rally (some stocks have performed very well during this rally, while others have remained stagnate QLGC/BRCD is a great example that used to oscillate between a ratio that doesn't exist any more)...prior to that we were in a definitive downtrend. The same people would also argue why would anyone trade a pair in a bull or bear market...when you could just go long or short and not suffer the loss of the hedge?? It just depends on your system...and your ability to forecast trend changes.
Statistical models I believe work best, in most any market....here is why:
Consider a ratio that moves along up or down randomly. That price channel is contained in some measurable pattern (use 2 standard deviations for example)...up, down, sideways whatever...
Then all the sudden something unusual happens....the ratio is outside the norm. Several things can happen that can correct the situation: 1) The long can move 2) the short can move 3)They can both move such that they are now back inside the range. Those who try to 'leg-into' the pair are likely missing half (or all) of the move. If your bias toward the trend of the pair is upward, and you buy the long when the ratio is out of whack, legging into the pair with the intention of shorting when prices are more favorable, you could easily miss the short move that causes the RATIO to come BACK INTO WHACK.
Good luck,
PT