Quote from libertad:
Every price movement has a reason...and a place to go..
And is definitely not random...To suggest that price movement has no reason...can only come from a fool...
Correct, like someone who makes a trade that moves the market because he is drunk like a skunk. But, tell me, even though the reason is "the pratt is drunk - or - he wants to get this trade in quickly, in order to get a cheeky shag from the bimbette he just picked-up", does this appear as a random event or as a deterministic phenomenon to the outside observer unaware of the inebriated(/shag) state of some Joe_NQ_drunk_Trader?
Read that again...
...outside observer...
If you think that some spike like the one described above is not random, then you must be smoking some exquisite stuff. If you were a HF trader and that spike took out your stops, then you got shagged. Random, or deterministic? Hmm... Perhaps deterministic to take out your stops... or wait, was the pratt drunk?
Of course, in the scheme of things, such a trade in isolation (regardless of its size) would probably (though not always) have little effect on the longer term price trajectory.
Read that again...
...longer term price trajectory...
So I guess it all comes down to this:
- Are prices deterministic or random - to the outside observer - accross ALL TIMEFRAMES OF OBSERVATION?
- What is is random?
- What is deterministic?
- Are some timeframes better than others?
Hmm...
A. There is a reason for every single trade ever made - regardless of how silly the reason might be - i.e. not all trades are ...ahem... "rational" events.
A2. You have no hope of knowing the reason behind every trade.
A3. There is no way you can know this a-priori, unless of course you are afflicted with an acute case of
Crystal Balliitis.
Q. Given A, A2, and A3, can you still profit from the market?
A. Yes.
A2. Shhh, you are giving too much away!
A3. OK.
Chill-out.
PS. ...and my glass is empty, so I need a refill of Jim Beam...

PPS. I am amazed I can even produce such a Deterministically-Random-Rant given my inebriated state