Quote from Thumama:
Couldn't agree more except for the trick.
Testing randomness must cover the whole time-series. Slicing the series into predetermined parts will surely produce trends and lead to the rejection of randomness. The questions are where do you make the cut and what's the length of each part. Ironically, the timing and length of those parts are random themselves !
I can not switch between random and nonrandom mode for any time-series because switching time is random itself.
Quote from Brandonf:
No, I dont mean a sideways market. The market can be just as random in a trend as it can be unrandom when its moving sideways.
Quote from MAESTRO:
If I tossed a coin and it landed 12 times on a row showing heads does that mean I am in a"head trend" ?![]()
Another good example is that if you take 1000 coins and flip them, each time removing every coin that comes up tails, eventually you might have a coin that turned heards 10 or 11 or more times in a row. That fact does not change the odds of the next toss, although it seems like a lot of people in the market seem to think it does.Quote from Brandonf:
ObviouslyAnother good example is that if you take 1000 coins and flip them, each time removing every coin that comes up tails, eventually you might have a coin that turned heards 10 or 11 or more times in a row. That fact does not change the odds of the next toss, although it seems like a lot of people in the market seem to think it does.
Quote from Thumama:
Hi..
Assume that the market is efficient and that prices move randomly.
1. For any stock, test the randomness of its price moves. There are many tests for randomness: for example, use the variance ratio test.
2. If the value of the variance ratio test indicates a nonrandom behavior of the time series, extend the time series by adding values ( future prices) that will force the variance ratio test to indicate a random walk. (revert to its expected value)
3. Try this for different timeframes and on average you get some abnormal returns.
I am just thinking..
Any thought?
Quote from Brandonf:
ObviouslyAnother good example is that if you take 1000 coins and flip them, each time removing every coin that comes up tails, eventually you might have a coin that turned heards 10 or 11 or more times in a row. That fact does not change the odds of the next toss, although it seems like a lot of people in the market seem to think it does.