Also this of course depends on your trade style but, if you don't see a change in an opposite direction cut your losses and get rid of em. HOwever, if you feel as if there is information unknown that would sway a decision to change the stock price, you could wait if you feel the loss is too big to live with.
i.e. if a stock's price has dropped rapidly because it's known that instead of being in 3000 theaters it will only be in 1500, maybe it might be time to just cut the losses and let it go. however, if it's something like, an MTC score comes out and is 3 million lower than what the current stock price is at, then it might be something to just hold on.
of course, if you are the type of guy who plays every change in the stock, like you are playing the trends in the exchange, you should be shorting stuff that is dropping now, and you should be going long on things that are improving... but that is a day to day thing and it doesn't seem like how you are playing