How about this Level 1 trading strategy?

[Ms Varima-Garch]

Quote from mizhael:

Suppose I could try to get an estimate about the following probabilities:

given the current stock price, what's the probability that the next transaction raises the stock price, or decreases the stock price.

The above is intra-day at about time precision of seconds...

Then I will buy when the stock price is expected to be up, and sell when the stock price is expected to be down.

Any comments about this trading strategy?

i don't know what you mean by next transaction per se.

the idea seems to be a variation on the martingale betting strategy, which, in a nutshell, is: the longer the string of losses (for example, string of down days in a market), the more likely the next bet to be a winner (up day in the market). so you increase the bet each time you lose . . .

nice try. it's an interesting mathematical concept, but it's not a reliably money management technique, the risk of ruin is very high. . .

see kaufman, chapter 22, theory of runs. it's even been programmed, but i am not know if it work in the real pracitce

Varima Garch