Nor was there any correlation between the size of index funds in particular commodities and the price rise for those raw materials.

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Once you know the average return, the standard deviation of each index and the correlation coefficient between each pair of indexes, the rest is math.

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The Russell 2000 value index had the highest correlation and, in fact, outperformed the median fund in both the private equity and VC categories.

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Since the spike in market volatility that started in the middle of July, the correlation between ICON and a diversified synthetic index of retailers that we put together has soared.

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Going frontier means adding lesser correlated assets to your portfolio, as the MSCI Frontier Markets Index shows 0.64 correlation to the developed markets and only 0.59 to the larger emerging markets in the EEM, according to Jackass Investing.

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This time around, writes Colas, all sectors moved up pretty much in lockstep with the benchmark index, expressing a much higher correlation (the trend that stocks will move up alongside external market movements, but not necessarily as a direct result of them) than usual.

FORBES: Let's Talk About Correlation

The underlying Solactive Global Oil Equities Index tracks the performance of 25 equal-weighted companies that have shown a high correlation to the spot price of oil.

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The index has a global mandate, but only North American stocks passed the most recent correlation screen with 80% currently allocated to the U.S. and 20% to Canada.

FORBES: Two New Oil And Gold ETFs To Watch