January 7th, 2017

Playing the Stock Market Game: Time is All

People don't see how easy it could be to do more, if only they gave it more time. The ultimate objective is to outperform long term averages, and making sure you do. So, here is a back to the basics.

You give yourself the job to go from point A to point B. Nobody is forcing you on this, that is to play this game. You already know your point A, that is where you are right now; with all your resources, know how, and expertise. You know where you want to go. The only thing left is to determine the path to get there. And here Google Earth or a GPS won't help you.

Academic portfolio management literature since the 60's will point out that the long term expected outcome of your endeavor will, in probability, end up to be about the same as secular averages. And, by this is meant no alpha generation expected, which in turn means, doing almost nothing or everything, you should expect to get about the same as most other people (the average).

In the stock market game, the short term trader is at a real disadvantage. As if his choice was to literally gamble his way out, under uncertainty, as if playing in a casino thinking that he can beat the odds, outsmart everyone, even the market itself. Surprisingly, he might even be lucky at it too. But he will have to use his special kind of math that only works for him until it doesn't. We could call it dream math, for lack of a better word, which has the peculiar property of having a much higher guessed at expectancy than the underlying probability. A way of saying that future claims are much higher than what reality might currently permit or admit (aka self-hype).

Or, he could make a plan of where he wants to go, gamble along the way knowing he will eventually get to point B. As if implying that if you only gamble, you might not reach point B at all. A visit of the gambler's ruin theorem might bring more light to this. Playing a game where you are doomed and not knowing it, does it spare you from doom?

Nonetheless, the method of play is a matter of choice. Some like the gambling for its entertainment value no matter what, and view having a long term plan as a boring restraint to their undertaking and enjoyment if ever there was one.

The trader/investor making a plan gets the advantage, and has a considerably higher probability of reaching his destination. He can see point B at the horizon and figure out how he will get there the most efficiently possible. It does not mean he won't take, or enjoy, some entertainment along the way.

In building a stock portfolio, an investor is faced with the same kind of problem. The most simple way I can express this quest, for any type of investor/trader, is with the equation: A(t) = A(0) + n∙u∙PT, which says: point B = A(t), is the destination. While the starting point: A = A(0), is from where one needs to engage on his/her path to accumulate: n∙u∙PT in net profits.

You want to play the stock market casino, you better understand those 3 numbers: n∙u∙PT, since to reach point B from point A you have to walk the path: A(t) - A(0) = n∙u∙PT. One thing you will realize trading over the short term is that point B needs to be far far away. You want to make it not only worthwhile but also reachable, a compromise of sort. It will require quite a lot of time.

Making a thousand dollar profit on a trade is not reaching point B. It is only reaching n = 1. How many more will you need to reach your goal, and how long will it take? Those are your real questions.

No matter how long you will trade, with whatever amount you started with, using whatever trading methods generating whatever number of trades, the above equation will still prevail. It is not a matter of opinion, taste, secret sauce, or something.

A two-minute course would be sufficient to explain its limitations. You have an equal sign on the table which says (viewed from that equal sign): that is all there is. Any trading strategy can be resumed using those 3 portfolio metrics.

If, at anytime you reach A(t) < 0, you will have lost the game. Which is probably why point B is identified as: A(t), as some future goal, a distant outcome. Reaching your termination time, you can only have n∙u∙PT more (or less) in your trading account than what you started with.

This also implies that your trading strategy has a signature: this is all it does. This is how it sliced and diced those price series and generated: n∙u∙PT in profits or losses. It will depend on if you had an edge or not: PT > 0? And how long did this edge last?

For instance, if you design a trading strategy, do a 10-year backtest and obtain: A(t) = A(0) + n∙u∙PT. Then, a 20-year test should simply double the outcome. It took 10 years to generate n trades, in 20 years it should generate twice as much. If it does not, you know the pillars and foundation of your trading strategy are cracked. If your trading strategy breaks down, there are reasons for that. You better find out why, because the next 10 years are at stake.

... to be continued...


Created... January 7th, 2017 © Guy R. Fleury. All rights reserved  

 

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