3-Hull-Spread - cross-instrument Indicator of market Spread of 3 (three) different instruments via building visual iChannel (see the equation below) that is changing its Width proportionally to the input from each instrument ("Statistical Arbitrage" based on Hull MA =HMA).

Core principle: price lines following the prices of "their" symbols after each discrepancy, constantly tending to return to the total of "synthetic" central. In other words, a system of 3 "related" instruments//pairs constantly strives to revert to their mean (so called "mean-reversion" effect).

• Works on any Instrument/TF (must open Charts/TF for all instruments used)
• Synchronization in place. After current bar is closed -- No re-paint / No re-draw
• "SetIndexBuffer" available for all variables (can be used in EA)
• Autodetect 4- and 5-digit prices

The following formulas have been used to build iChannel:

• Price-line Symbol-1 HMA(1)_Fast / HMA(1)_Slow (chart where Indicator is turned on)
• Price-line Symbol-2 HMA(2)_Fast / HMA(2)_Slow (plus "reversal=true" Mode for instruments with negative correlation)
• Price-line Symbol-3 HMA(3)_Fast / HMA(3)_Slow (рlus "reversal=true" Mode for instruments with negative correlation)

• Middle-line М = "synthetic" central (S1 + S2 + S3)/3 (yellow dotted line)
• iChannel = (S1-M) + (S2-M) + (S3-M) (red and green dots)

This formula allows to combine various instruments on one chart (see Fig. 1), for example:

• XAUUSD ~1100
• AUDUSD ~0.7
• USDCAD ~1.33

Conditions for Signal:

#1. Width of iChannel started to narrow (first green dot after series of red dots)

#2. Width of iChannel > Level

#3. Price Line S1 is on one side of Middle-line М, аnd Price Lines S2 and S3 - are on the opposite side of Middle-line М -- as following:

• Signal BUY Symbol-1: S1<M S2>M S3>M -- NOTE: iChannel width (red and green dots) is changing wider or narrower
• Signal SELL Symbol-1: S1>M S2<M S3<M -- NOTE: iChannel width (red and green dots) is changing wider or narrower

Parameters

• Inp_Fast_HMA - period of Fast moving average
• Inp_Slow_HMA - period of Slow moving average
• Inp_MA_Method - parameter of Hull MA
• Inp_MA_PriceType - parameter of Hull MA

• Inp_Symbol_1 - Symbol-1 (by default GBPJPY)
• Inp_Symbol_2 - Symbol-2 (by default EURJPY)
• Inp_S2_revers - =True in case Symbol-2 has negative correlation to Symbol-1
• Inp_Symbol_3 - Symbol-3 (by default CHFJPY)
• Inp_S3_revers - =True in case Symbol-3 has negative correlation to Symbol-1

Other Useful Information

Typical EXAMPLES of highly correlated 3-way instruments:

• GOLD vs. gold-forming currency pairs AUDUSD, USDCAD and NZDUSD
• GOLD vs. Crude/WTI and Brent/BRN
• Stocks vs. Indices (S&P500, NASDAQ, DJIA etc.)
• Soybean Meal March 2016 (ZMH16) vs Soybean Oil March 2016 (ZLH16) vs Soybeans March 2016 (ZSH16), etc.

Complete list of 120 classic 3-way combinations of currency pairs - see link in the Comments section.

NOTE: for classic 3-way combinations (where participating 3 currencies only) - Middle-line М will be always a straight line.