The Implied Correlation Index does not calculate the correlations among the entire S&P 500 index. Instead, it utilizes a “tracking basket” of the 50 largest components of the SPX as measured by market capitalization. For more on the calculations involved in the Implied Correlation Index and related materials, check out the Implied Correlation Index splash page, the Implied Correlation Index white paper and historical data going back to the beginning of 2007.
I will discuss this index on the blog going forward, as it is clearly an important piece of the VIX valuation mystery. For now, readers may be interested to see how SPX component correlations (blue line) have compared with the VIX (red line) during the recent bear market.
[source: CBOE]
And then there's this correlation between the SPX and the VIX that's been characteristic of the bear run since 12/07.
ReplyDeletehttp://bzbtrader.blogspot.com/2009/07/when-vix-and-spy-move-together.html