Figure 30
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As shown in Figure 31, trend following indicators do not work well in sideways markets.
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Another class of indicators are "leading" indicators. These indicators help you profit by predicting what prices will do next. Leading indicators provide greater rewards at the expense of increased risk. They perform best in sideways, "trading" markets.
Leading indicators typically work by measuring how "overbought" or "oversold" a security is. This is done with the assumption that a security that is "oversold" will bounce back. [See Figure 32.]
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What type of indicators you use, leading or lagging, is a matter of personal preference. It has been my experience that most investors (including me) are better at following trends than predicting them. Thus, I personally prefer trend following indicators. However, I have met many successful investors who prefer leading indicators.