continuing the current Octover 2005 article.... (there's a limit of characters on each post to being under 10,000 words, so I had to break up the article into pieces)....
continuing article
Some Constraints
The aforementioned list of day-trading approaches is far from comprehensive. In fact, there are hundreds, if not thousands of combinations and permutations for each method or combination of methods that can and do fill books. Without going into the merits of any methodology, all day trading suffers from the same constraint â time. Day trading involves executing strategies within highly limited timeframes. The longest is from open to close. The shortest can be a few seconds. In all cases, once the time limit is imposed, there is no flexibility unless the day trade is extended to the following dayâs (or nightâs) session, in which case it no longer is a day trade. Given the time constraint, an obvious pitfall is any potential lack of price movement within the defined interval. If a trade cannot be completed within the allotted time interval, it must be abandoned.
In addition to the time constraint problem is the problem of transaction velocity. There are two facets of transaction velocity. First, of course, transaction velocity is associated with trading frequency, and the more frequent the trading, the higher the transaction costs. The second aspect of transaction velocity, often ignored, is apparent only when trading is ongoing. As alluded to at the beginning of this article, there is a physical process required to formulate, enter and exit a trade. Some models are too sensitive to allow a realistic physical market entry and exit.
As an example, I recall a system Iâll call âXâ to avoid casting aspersions on the creative process of the systemâs inventor. System X dates back to the introduction of handheld programmable calculators. A day-trading system was programmed into a handheld that consistently identified $0.02 price movements in soybean futures. The problem was that the $0.02 moves would come and go before a trader could post the entry and exit orders. The computer simulation then assumed you had executed a trade when, in fact, you were out when you were supposed to be in and in when you were supposed to be out!
More emphasis, by far, has been placed on day-trading transaction costs. Although rates can be negotiated down to bare bones, even at the lowest cost levels a high-velocity system can chew up profits with commissions. This is why many day-trading systems that look great on paper turn out to be duds when used in real markets with real commission costs.
Fortunately, a growing emphasis is being placed on physical demands of day-trading, which includes time required to execute entries and exits. The common term associated with this, of course, is slippage. In many cases, by the time a trader has identified a trade, entered the order, received a fill and calculated an exit, the intended transaction has been missed. Even if not completely missed, there can be considerable erosion between the amount anticipated and the amount realized. If this is characteristic of the day traderâs approach, profitability will be negatively skewed.
Physical demands also include the routine of getting up every morning, mounting the saddle and riding the market from beginning to end. It may sound easy, but day trading can be extremely exhausting. Unless you have nerves of steel and a cast-iron stomach, day trading will extract a physical toll. Among the exhaustion symptoms I have experienced or witnessed friends and associates experiencing are headaches, digestive problems, sleeping disorders, tension or anxiety, irritability, delusion and depression.