Tortured data - buyer beware

skill and luck

This thread seems to have rambled off a little. But to some recent points:

Duke, that is very interesting that the CPC code bans back-testing of products, but does not extend this to the underlying indices/strategies. That’s a rather large loophole for the regulator to have left. One product providers would be silly not to exploit.


Ecstatic, to your point about skill and luck; Poker most definitely is a game of skill as you say. But, like fund management, it also involves luck. And the paradox of luck is that in highly skilled environments, luck plays an even larger role. So I can quite confidently say, that at the final table of the world series of poker, the ultimate winner will be the luckiest at the table (a statement which in no way detracts from the skill of any of the players at the table).


I don’t understand your martingale point about roulette. If you are suggesting doubling your bet in the expectation of eventual pay out, the existence of white (and double white on some wheels) plus table maximum bets makes this a very dangerous ‘strategy’. Likewise for blackjack, table maximums prevent this strategy working.

As to the various posts regarding the efficacy of trend following investment strategies. I am not sure if we could reconcile our investment philosophies. You appear to concentrate on trading of individual commodity futures, something I would consider to be closer to speculation than investment (which involves ownership of some underlying asset for a period of time long enough for fundamental value to reveal itself). Like the croupier at the casino’s poker table, the only long term winner at this game will be the market maker, those taking a consistent slice of the overall action. That is not to suggest you will not make money, but as Marc points out, there is no way for me to tell in advance whether that successful person will be you or someone else at the table.


To go back to the original point of this thread, which was the spurious causation drawn between simulated investment strategies and wonderful investment outcomes. An investor must ask him/herself if the investment proposition makes sense. You will never convince me that frequent trading of commodity futures is something at which I can consistently make money. Equally I remain unconvinced about the prospects for an algorithm which dictates when to buy ‘risk on’ assets and sell ‘risk off’ assets (admittedly a very basic summation of the BNP strategy within the Dolmen safe harbour product).


I am unconvinced. That is not to say it won't work. This product may be bailed out by a large dose of luck. But intelligent investing, recognising the role of luck in the eventual outcome, attempts to reduce its importance.


The idea that anyone can make money consistently trading markets is a fiction convenient only to stock broking and spread betting firms. Stock brokers and their ilk are in the main, profitable after all.
 
I do agree with a lot of the points from all posters but i digress on some!

"I don’t understand your martingale point about roulette. If you are suggesting doubling your bet in the expectation of eventual pay out, the existence of white (and double white on some wheels) plus table maximum bets makes this a very dangerous ‘strategy’. Likewise for blackjack, table maximums prevent this strategy working."

If you have an infinite amount of money to bet then you would eventually win. The problem arises as the roulette table usually has a fixed upper treshhold of betting (as in max bet 500 bucks). If i bet a million times and continue to use a martingale i will win eventually! (again depends on casino rule's). Roulette by itself doesnt define a max bet the casino rules do.

Indeed i agree with all your points including the 2 greens on a roulette giving an unfair advantage. However mathematically, and very much depending on the casino rules blackjack can give a slight edge to the person if for instance you could card count etc. This edge may be ever so slight so have to be executed brilliantly aswell as looking carefully at casino rules.

There is some luck alright in the winner which is why i suggested the final table is a better metric than the actual winner.

However if i trade 100 times a day for 6 years and am still in profit then i could have an edge (13200) trades for instance as the number of trades is not insignificant.

I also strongly agree brokers do sheckle there clients to bits and in fact there was an interesting case whereby a client of a large broker managed to figure out the brokers algorithim and tricked it into taking profits from the broker. This went to court and the client lost (which i find incredulous)!

Portfolio rebalancing is / can be a good thing as many of us know too heavy exposure to 1 asset class is/can be a dangerous thing!
 
ecstatic that's not my understanding of what a martingale is. My textbook says that it is a game, or a model of the financial markets where there are no biased strategies. No matter what your rules of engagement your expected outcome is the same - it will of course be different in delivery between different strategies - but each strategy has the same risk adjusted expectation from the beginning.

Martingale theory is very relevant here for what is being suggested with this product is that by very careful analysis of past performance a system has been devised to beat the market in the future.

Ever go into a Paddy Power shop?, he runs a lotto every 10 minutes and helpfully informs the punters of suggestive patterns from the last 30 spins - the screen blares at you the "hot" ball i.e. the one which has appeared most often. It also tells us the "cold" ball and points out various other wondrous patterns. I am sure the poor mugs all form different views as to which of these past observations are of most relevance to the imminent future.:(

In a somewhat more sophisticated manner this product is attempting to persuade gullible investors that the past holds the key to future free lunches on the markets.

I don't understand your casino point. For those unfamiliar it goes like this. Imagine a casino which offers even money on a single number in a roulette game. Shocking and criminal odds you say. But with unlimited resources you can follow a strategy which bets on a single number (can be different each time) and provided you bet enough to recoup past losses and win say a euro your number will eventually come up so that you will certainly finish winning a euro despite the dreadful odds. I don't think this adds much to the current discussion.
 
Martingale keep doubling until u win the only issue is money is a finite resource and they finitly cap your earnings. In this case dont complicate use red and black.

Funnily enough i have never been too a paddy power shop weird huh ?

The strategy is soundish for diversifcation component of a portfolio however as to whether us govvies and bundesbank govvies will be safe havens in 10 years is anyone's guess. Statistically speaking they will be but then again wasnt the GBP the powerhouse of the world until panama.

Will markets still be irrational and fear based yes they will as long as humans are involved.
 
ecstatic. two definitions of martingale in Wiki

[broken link removed]

and

Betting Strategy

A key quote from the first is:
Wiki said:
In probability theory, a martingale is a model of a fair game where knowledge of past events will never help to predict future winnings. Martingales exclude the possibility of winning strategies based on game history, and thus they are a model of fair games.
This seems very relevant to this debate. Not sure of the relevance of the second meaning, yours, is.
 
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