--------Quote from TheRumpledOne:
IN MY INBOX TODAY:
Find the Edge
Stockscores.com Perspectives for the week ending March 30, 2008
.....
The question is, do you have an edge in the market?
Are you trading a strategy that assures you a profit over a large number of trades? If you are serious about making money in the market, you should be able to define the expected out come of your trading strategy in the same way that a casino can predict their profitability from millions of dollars wagered in the pursuit of 21.
How do you calculate your edge? Simply:
((Profit of a successful trade times the probability of a successful trade) - (loss of an unsuccessful trade time the probability of an unsuccessful trade
As an example, a trade that has a 30% chance of making $5000 and a 70% chance of losing $1000 has an expected profitability of $800.
Here we see how even a trade that has the odds stacked against it is worth taking because it has a positive expected outcome.If you make this trade enough times, you will average $800 in profit per trade.
This means we need to set out on a study to determine the probabilities of profit and loss for a trading strategy. Establish a set of rules and then test them over a large sample of trades to determine the expected value of the trade.
But, if we find a trading strategy that has a profitable expected value, are we assured of success in the same way a casino is assured a profit hosting games of blackjack?
No. In blackjack, there are rules enforced by the casino. The player must give the casino their money if they go over 21. They must give their money if they have a hand that is lower than the dealer.
In trading, there is no one to enforce your well tested trading rules except you. In the heat of the trading moment, when you must decide whether to exit the trade at the stop loss point or hold out for a turnaround, it is only up to you. When you have the choice of selling for a profit or continuing to hold until you get the sell signal your strategy was tested for, it is only up to you.
And you, assuming you are a normal human being, are likely to break your own trading rules.
Why?
Because you avoid pain and pursue pleasure. You lack confidence in your strategy because of your recent experience. You think you can use your better judgment based on what you are seeing you now. You lose your focus.
These are the things that turn the relatively simple pursuit of making money in the market in to a frustrating, mind numbing and stressful process. Who is at fault?
Only You.
Excellent post The Rumpled One! IMHO, an understanding of these basic concepts and putting it into practice is truly the Holy Grail in trading. It is a recurring theme in many trading books and is explained over and over many times around but I think it can never be over emphasized as this is truly a game of probabilities and law of large numbers where risk management is key to survival.
-"Good traders manage risk, Great traders maximize opportunity"
