Hello Samanatha, Thanks for your post ... a good topic and thanks also to D and PS for additional leads and others for the discussion.
<snip> .... all trading systems will stop working forever at some point (because the inefficiency in the market they exploit will be killed by everybody jumping on board).<snip> This point of view isn't shared by all traders. There are at least two grounds for objection: - the massive number of possible permutations, at any point in time in the market, make the chance that two traders are doing the same thing with significant amounts of money are unlikely e.g. Aronson puts forward this idea in his book, "Evidence Based Technical Analysis". - based on the behaviour of market participants it is also unlikely that a significant number of traders will trade exactly the same trade even if it is "published in the Washington Post" e.g. one of the Wizards interviewed in one of Schwagers book's argues along those lines when he is asked if he is reluctant to talk about his trading methods. Take this topic for example ... how many people read the topic ... read it carefully ... read the links ... thought about it ... did some homework ... go on to study the system ... put it into practice (without changing anything) and then go onto to trade it in the same market, same instruments, same timeframe etc with significant amounts of money. I consider myself to be a trend trader but my definition of a trend is unlikely to be used by more than a handful of people ... the chance that others are watching the same trend, in the same instrument and the same timeframe is almost zilch. The caveat is if and when large institutional traders are systemic traders and/or algorithmic traders .... perhaps large players can mop up systems if they are interested enough to do so. There has been little discussion, on this board, about systematic trading by institutional players. Siddhartha did say he didn't observe that the practice was widespread in his time in the industry. On the other hand I recall reading an article that said Goldman Sachs were into algorithmic trading in a big way. As an aside ... I thought that the axiom "We will miss most of the growth if we miss the 10% biggest gain dayss in the market (ditto for a weekly/monthly/yearly basis etc) was basic (same for missing most of the losses if we avoid the worst ten%). Looking at any index chart, with hindsight, it seems obvious that there are several points where any number of indicators could have told us to get out and we would have been better off ... the trade off is the cost of exit and re-entry. I put a lot of effort into investigating that payoff/versus cost when deciding how often to trade (buy and hold versus, say, short term or day trading). I was surprized last year when so many in this forum (of all places) seem to be hurting. Re Momentum trading: There are two articles here on trend trading (scroll down to 3.1a and b. http://zboard.wordpress.com/library/miscellaneous-articles/ Michael Covel appears to be the current king of trend trading (I like his book but not his videos). www.TrendFollowing.com How do we know when a system is failing? We can't get a math measurement to tell us when that momement has arrived ... all models assume stationarity and as soon as it is broken we are in unknown territory .... classically a shift in the average value or the dispersion (of the trade series) signifies non-stationarity, although random data series contain a good deal of variance and it is hard to distinguish random variance from a system breakdown. However IMO most traders are trend traders and almost anything will work while we are on the right side of the trend .... so in the real world a system is broken when our assumptions about the underlying trend are incorrect. --- In [email protected], "samu_trading" <samu_trad...@...> wrote: > > All, > > In his really good book Quantitative Trading Systems, Howard states that all > trading systems will stop working forever at some point (because the > inefficiency in the market they exploit will be killed by everybody jumping > on board). > > On the other hand you have momentum / ROC based systems working forever now, > same for trend following MA crossover systems like The one propagated by > Mebane Faber. Momentum and MA rossover trendfollowing does seem to work > "forever". > > Any comments from the gurus here? > > Thanks, Samantha >
