Ged

[db said, "Yes, static charts are sufficient to answer the question..."] Thank you db. Appreciate you taking the time. Ged

db said, "What I said was that one could test entry and exit triggers in a couple of days." I mis-spoke, as the above is what I am referring to: entry and exit triggers. I must be approaching the test of these wrongly, as it seems to take me quite a while. I was doing replays and taking notes. Is viewing static charts sufficient for these? Ged Yes, static charts are sufficient to answer the question. If you know what a range is, what a breakout is, and what a retracement is, you can determine how far away from the trough or crest of the retracement you have to enter in order to determine the probability that the trade will be successful, i.e., how to avoid being too early and how to avoid being too late. These entries may change every day. They may change several times during the same session. But that's part of the challenge of reading price movement. It is also a large part of the reward. All of which sounds very kumbayah. But if you're afraid to take the trade at all, no amount of counting ticks is going to make you unafraid. Your time would be better spent determining what it is you're afraid of and why. If you're not afraid and the trade looks good, just take it. If it works out, great. If it doesn't, scratch it and move on to the next.

db, you mentioned that back testing can be done in an evening or two. It doesn't seem to work that way for me and I'm wondering if perhaps I'm going about it in the wrong way. You mentioned 50 to 100 samples as being the range you would consider. Did you mean in an evening or two one item could be back tested 50 to 100 times, retrace entries on a BO for example? Are you anticipating a static chart 'back test' or a replay back test of each item? I have assumed the latter, but I don't see how that could be done in an evening or two, complete with notes, etc. All that you can share to elucidate best procedures will be greatly appreciated. (My apologies if you answered this before.) Thanks much, Ged I didn't say backtesting could be done in an evening or two. Backtesting could take months. What I said was that one could test entry and exit triggers in a couple of days. As to your other questions about backtesting, I have no idea what you're doing so I can't give a pertinent answer. If you're trading the SLA/AMT, no backtesting is necessary. Or forwardtesting, for that matter. It's all been done. However, if you can't or don't want to follow the rules but would rather come up with something of your own, then you'll have to start at the beginning with observation.

I appreciate the response Siuya. I have speculated about some of the possibilities, but would like to know what I am actually looking at. The tape always reflects that one trader initiated the transaction. Also, quite often this trade seems to receive a slightly better than market price (a few pennies). Thanks again.

With regard to AAPL, 99% of the time, at the opening bell, the first transaction is a purchase or sale of a large block of shares (usually between 50,000 and 300,000 shares; sometimes as large as 800,000 +/- shares). Does anyone know what these transactions actually are?