On Feb 9, 2011, at 1:25 PM, Jordan Hayes wrote:
> I have to correct something key in this thread: when a trade occurs, it is true that the buyer and the seller are exchanging an equal amount. But: in the moment just before the trade, there was a gap between what the "best bid" is willing to pay and the "best ask" was willing to accept. At the moment of the trade, one of them blinked. Either the buyer was willing to buy-up; or the seller was willing to sell-down. So while it's true that the price was "the same" -- the expectation was not.
In liquid markets, the bid/ask spread is rather tiny, no?