OBV指標

平衡交易量指標(OBV)是由 Joseph Granville 開發，在他的《每日股票市場獲最大利益之戰略》一書中有所描述。OBV通過對比價格與成交量來判定集聚或分散的程度。如果收盤價升高，那麼該指標將會加上成交量；如果收盤價降低，則該指標減去交易量。如果收盤價未發生改變，那麼交易指標也不發生變化。

交易信號
OBV指標應該與別的指標結合起來使用。

盤整期
註意盤整期OBV的上升或下降趨勢：
• OBV上升是對價格向上突破的預警。
• OBV下降則預示著價格有可能向下突破。

單邊市場
上升的OBV是對市場上升趨勢的確認，下降的OBV是對下降趨勢的確認。
• OBV的看漲背離警示價格已經達到底部。
• 看跌背離則說明價格探頂。
 
示例
英特爾公司股價以及  OBV指標

1. 在看跌背離出現之前，價格橫向波動。背離信號十分的微弱——OBV走出了較低的高點，而價格則與前期高點持平。
2. [1] 處的信號似乎不正確——價格走出了新高——但接下來OBV出現三重看跌背離，進一步說明了趨勢的上升動力殆盡。
3. 進一步的看跌背離出現——價格沒有突破前期高點，OBV的高點進一步降低。不久之後，價格急速下降。

公式
OBV的計算步驟如下：
1. 如果收盤價升高：
           OBV = OBV [前期] + 成交量 [當前]
2. 如果收盤價降低：
           OBV = OBV [前期] – 成交量 [當前]
3. 如果收盤價持平：
           OBV = OBV [前期]

On Balance Volume
The On Balance Volume (OBV) indicator was developed by Joseph Granville and is explained in his book Granville's New Strategy of Daily Stock Market Timing for Maximum Profit.

On Balance Volume attempts to measure the level of accumulation or distribution by comparing volume to price movements. Volume is added to the indicator if closing price moves up and subtracted if closing price moves down. No adjustment is made if closing price is unchanged.
Trading Signals
On Balance Volume should be used in conjunction with other indicators.
Ranging market
During a ranging market watch for a rising or falling On Balance Volume:
• Rising OBV warns of an upward breakout.
• Falling OBV warns of a downward breakout.
Trending Market
A rising On Balance Volume confirms an up-trend and a falling OBV confirms a down-trend.
• Bullish divergence between OBV and price warns of market bottoms.
• Bearish divergence between OBV and price warns of market tops.
 
EXAMPLE
Intel Corporation plotted with   On Balance Volume.
1. Price trades in a range during March before a bearish divergence occurs. The signal is fairly weak - price makes an equal high while On Balance Volume makes a lower high.
2. The signal at [1] appears to have been incorrect - price rises to a higher peak - but a far stronger triple divergence (price makes a higher high while OBV makes a lower high) signals weakness.
3. A further bearish divergence occurs - price makes an equal high and OBV makes a lower high. Shortly thereafter price falls sharply.
Formula
Steps in the On Balance Volume (OBV) calculation are as follows:
1. If Close for the period is higher than the previous Close:
           OBV = OBV [previous period] + Volume [current period]
2. If Close for the period is lower than the previous Close:
           OBV = OBV [previous period] - Volume [current period]
3. If Close for the period is equal to the previous Close:
           OBV = OBV [previous period]

本文翻譯由兄弟財經提供

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