平均动向指标是Welles Wilder发明的定向运动系统指标的一部分，它可以显示股价是处于调整期还是趋势中。
ADX 信号
趋势改变
当14日ADX指标线走势向下，但在40之上时说明趋势走弱。需要注意的是，ADX指标只是显示趋势的强弱——而不是趋势的方向。建议您将它配合别的趋势指标使用，比如动向指标或者移动平均线等。
市场处于趋势中还是调整期
• ADX低于20说明市场处于调整期；
• ADX 大于20且向上增长，显示一个新趋势的开始；
• 如果ADX突破后紧接着一个失败的反弹，说明趋势在加强。
• ADX大于40显示趋势陡峭上升，但接下来通常会面临一轮反弹。
示例
苹果公司股票[AAPL]及其对应的平均动向指标（14天）和14天动能摆荡指标。
1. 当ADX大于20，动能摆荡指标低于0时做空。
2. ADX 大于 40，但走势向下，预警趋势减弱。
3. 动能摆荡指标向上穿过0时平仓。
4. ADX 一直维持 20以下，显示市场处于调整期。
5. 动能摆荡指标大于0、ADX 向上穿过20时做多。
6. 当 ADX重新恢复在20之上，动能摆荡指标仍然大于0时加仓做多。
7. 动能摆荡指标向下穿过0时平仓。
ADX - Average Directional Index
ADX is part of the Directional Movement System developed by J. Welles Wilder but can be successfully used on its own to signal trend changes and to indicate whether a stock is trending or ranging.
ADX Signals
Trend Changes
A weakening trend is signaled when 14-day ADX turns down while above 40. Note that ADX only indicates trend strength — not trend direction. It may be wise to supplement ADX with a trend filter, whether directional movement or a moving average, to signal direction.
Trending or Ranging Markets
• ADX below 20 for any length of time indicates a ranging market;
• ADX rising above 20 indicates the start of a new trend;
• The trend signal is strengthened if ADX breakout is followed by a failed swing;
• ADX above 40 indicates a steep trend, but often precedes a reversal.
EXAMPLE
Apple Inc. [AAPL] is displayed with Average Directional Index (14 days) and 14-day Twiggs Momentum as a trend filter.
1. Go short when ADX rises above 20 and Momentum is below zero.
2. ADX down-turn above 40 warns that the trend is weakening.
3. Exit when Momentum crosses above zero.
4. ADX holding below 20 indicates a ranging market.
5. Go long when ADX rises above 20 and Momentum is above zero.
6. Increase position when ADX recovers above 20 and Momentum still above zero.
7. Exit when Momentum crosses below zero.
本文翻译由兄弟财经提供
文章来源：http://www.incrediblecharts.com/indicators/adx-average_directional_index.php