How do you define a dip? 4, 6 or 8 points pullback from the high or, a break of overnight low or, something else? I was taught to buy pullbacks but my definition of pullback isn't getting me in the market. This can't be random. I have been here for a long-time and EqtTrdr has been saying this since 2003-04.
That's the beauty of the whole thing. It doesn't matter what your definition is for your trading style. You can buy 1pt dips, 5 pt dips, 100pt dips..etc, on whatever index you like.
You have to find dips that work for the market you face and its current conditions. Maybe it has to reach an ema. Maybe it has to push a stoch to a certain level. Maybe the price action has to look like xxxx. Maybe you have some volume conditions in it. Only your own definition can be tested, proven, and then traded.
=================== True & kiwi-T had some good points. Buying dips is for uptrends, better measured than defined, as kiwi said moving averages help. Buying a 100 point dip in SPY would almost certainly be in a bear trend;probably better off selling dip then. And while ES,SPY,DIA YM are in strong uptrends; unless one has been profitable lately, its more risky buying dips now simply because even best uptrends get extended. Profitable traders may hold thru it.