Visit this thread and become knowledgeable. Thanks ET!!!!!!!! http://www.elitetrader.com/vb/showthread.php?threadid=84330
How straight a line do you want to draw, and by what criteria? A good trendline is straight and may carry on for quite some time, whatever your timeframe - minutes, hours, days, weeks. There will be reactions w/in that trend as price bounces off and tests the line but that is its nature; mkts move, rest, move, rest. Trend and consolidation/reaction, the latter absorbs the former and prepares for another move till that new trend exhausts itself and must settle down once again, and the cycle goes on... Price is decided by, whom else, the mkt participants. They are the ones doing the buying and selling. In an auction mkt price is determined by the perceived value of the particular commodity. In the simplest terms, if you're standing before a podium selling Beatle's bobble-head dolls on any average day, and you have only 100 of them, the auctioning process will go different than if you had 1000. Or say you're a cold-hearted, greedy bastard and you hold the same auction the day after John Lennon was shot. The 100 would probably be much more valuable at that time than most any other, as would the 1000. Common sense. Such is the nature of supply and demand and the perception of value. If something is "dear", for whatever reason, be it lack of supply or perceived value, or some combination thereof, there is demand, price goes up; if there is abundance, supply, or lack of demand due to perceived value, price will falter. Sorry if this seems rudimentary, I may have misunderstood you, but you seem to ask very basic questions, and I haven't really seen them addressed in this thread. H