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Lesson 2 <object width="425" height="373"><param name="movie" value="http://www.youtube.com/v/XCcg7a1XR2E&hl=en&color1=0x234900&color2=0x4e9e00&border=1"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/XCcg7a1XR2E&hl=en&color1=0x234900&color2=0x4e9e00&border=1" type="application/x-shockwave-flash" wmode="transparent" width="425" height="373"></embed></object>
Like any other technical indicator, MACD does not have any "effect". It's the other way around: when the market moves, it affects the indicators. In other words, the market doesn't look at MACD to figure out where it wants to move next. Instead, MACD records where the market is. More specifically, MACD is positive when the short term average is above the long term average and is negative otherwise.
I find MACD is more useful in time chart than in tick or volume chart the MACD cross the zero line regularly in time chart but it cross the zero line unregularly in tick chart you do not know where the price will go in tick chart
MACD can be used if you limit your loss and let the win run but as soon as you figure that, you'll throw away MACD some guys have custom made indics and they ain't for ya to see or use