Bollinger Band Gap.afl
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- //------------------------------------------------------------------------------
- //
- // Formula Name: Bollinger Band Gap
- // Author/Uploader: klaushengher
- // E-mail:
- // Date/Time Added: 2003-06-15 12:43:31
- // Origin:
- // Keywords:
- // Level: advanced
- // Flags: exploration
- // Formula URL: http://www.amibroker.com/library/formula.php?id=287
- // Details URL: http://www.amibroker.com/library/detail.php?id=287
- //
- //------------------------------------------------------------------------------
- //
- // BbandGap - How to Make Money Shorting Stocks in Up and Down Markets
- //
- //------------------------------------------------------------------------------
- /* BbandGap. Written by Klaus Hengher
- based on Tools and Tactics for the Master Day Trader
-
- Velez, Capra (Pristine)
- BbandGap - How to Make Money Shorting Stocks in Up and Down Markets
- The Set Up
- 1) The stock must first puncture and close outside (above) the upper Bollinger
- Band. The closer the closing price is to the high of the day, the better.
- And the bigger the day's advance, the better. As a general rule, you will
- want this day's bar to be at least $2 or more in length from high to low.
- This is not always necessary, but it's better to have it.
- 2) On the following day, the stock must 'gap' down below the prior day's close.
- This 'gap down' is crucial as it serves as the most important criteria of
- the entire strategy. If the stock does not open for trading below the prior
- day's close by at least 50 cents (preferably more), no action should be
- taken. We need weakness right at the open. Example: If on Tuesday the stock
- closed at $40, we want to see the stock open for trading on Wednesday no
- higher than $39.50. It must open down!
- Note: In many cases, this gap down will be caused by either an exceptionally
- weak market open or a negative news item on the company, such as a brokerage
- downgrade.
- But in either case, the gap down signifies major selling (profit taking),
- and the pros who short will be loving it. Keep in mind that both the above
- criteria must be met before action is taken.
- The Action
- Once the above Set Up Criteria is met, the trader will do the following:
- 1) Sell the stock short (at the market if you have the luxury of being able to
- kill the trade instantly in the event the stock gets too far away from you).
- With order entry systems like The Executioner(r), the trader will be able to
- instantly cancel the open order, if need be. If the trader lacks this
- 'instant canceling' capability, he is better off placing a limit sell order.
- 2) Once the short has been filled, place a protective stop 1/8 above the high
- of the prior day. This is our insurance policy against disaster. If the
- stock rises above the high of the prior day, that is our sign that the
- shorts are being squeezed, and the major advance has more steam left, as
- those short will be forced to buy at higher prices to curtail their losses.
- 3) Hold for two to three days or more, protecting your profits on the way down
- with some form of trailing stop methodology. Note: Some traders may want to
- move their protective stop 1/8 above each prior day's high. This is called
- 'tracking the prior highs.' Others may want to 'book profits' in the
- following manner: 'Once up $1, move stop to break-even. Once up $2, protect
- 1/2 of the gain, and once up $3 or more, protect 2/3 of the gain.
- Note: The idea is to ride the short for maximum profits. But of course if
- the trader is shorting a weak stock in the context of a bullish market
- environment, booking the profits sooner rather than later is preferred, even
- if it means missing additional gains.
- }
- */
- fClose = Ref(C,-1);
- fHigh = Ref(H,-1);
- fLow = Ref(L,-1);
- fAdvDrop = fClose - Ref(C,-2);
- fAtr = Ref(ATR(8),-1);
- diffHl = fHigh-fLow;
- fStoch = Ref(StochD(14),-1);
- fBBandTop=Ref(BBandTop(C,20,2),-1);
- fOpenCond = fClose - 0.5 * fAtr;
- fOpen = Ref(O,0);
- fStopLoss = fHigh + 0.5 * fAtr;
- bbTopSell =
- // The stock must first puncture and close outside (above) the upper Bollinger Band
- IIf( fClose > fBBandTop AND
- // The closer the closing price is to the high of the day, the better.
- fClose > (fLow + 0.75 * diffHL ) AND
- // And the bigger the day's advance, the better
- fAdvDrop > (1.5 * fAtr) AND
- // On the following day, the stock must 'gap' down below the prior day's close.
- // This 'gap down' is crucial as it serves as the most important criteria of
- // the entire strategy.
- fOpen < fOpenCond AND
- // Overbought condition added
- fStoch > 80, 1, 0 );
- /* Exploration Columns for Sorting */
- NumColumns = 10;
- Column0 = fOpen;
- Column1 = fOpenCond;
- Column2 = fStopLoss;
- Column0Name = "Open";
- Column1Name = "OpenCond";
- Column2Name = "StopLoss";
- Column0Format = 1.2;
- Column1Format = 1.2;
- Column2Format = 1.2;
- Filter = bbTopSell == 1;
- Buy = 0;
- Sell = bbTopSell>0;