Originally Posted by
ratkin
It is the same tactic traders use to bully people on betfair. Put in big sell orders just above current price and all the nervous small players jump in front and sell, creates its own momentum, then the big player suddenly switches sides and buys up big at the lower price, and repeats the scenario on the way up. Basically herding all the small sheep.
It easier in stocks as they know where all the stop losses are and that the small sheep are all watching the popular moving averages etc, so they force the price below them creating a technical sell that tricks all the amateurs. It the reason many small traders now have such a hard time, they are manipulated by machines