Paul Tudor Jones
Don’t ever average losers. Decrease your trading volume when you are trading poorly; increase your trading volume when you are trading well. Never trade in situations where you don’t have control. For example, I don’t risk significant amounts of money in front of key reports, since that is gambling, not trading.
If you have a losing position that is making you uncomfortable, the solution is very simple: Get out, because you always get back in. There is nothing better than a fresh start.
Don’t be too concerned with where you got into a position. The only relevant question is whether you are bullish or bearish on the position that day.