The CBOE volatility index VIX is the most important volatility market measure, sometimes called the "fear index. Download the VIX data (vi) for the last three months, and compare them with the 30-day SPX moving average return volatility. More specifically, the moving average return volatility on day i can be estimated by 252 ; = 100 x (R, - R.)2 29 j=-29 where Ri = (S; - Si-1)/S; 1 is the return of SPX on day i, and Ri 1 30 j=i 29 R, Comment on the relations and differences between these two time series (i, vi). The CBOE volatility index VIX is the most important volatility market measure, sometimes called the "fear index. Download the VIX data (vi) for the last three months, and compare them with the 30-day SPX moving average return volatility. More specifically, the moving average return volatility on day i can be estimated by 252 ; = 100 x (R, - R.)2 29 j=-29 where Ri = (S; - Si-1)/S; 1 is the return of SPX on day i, and Ri 1 30 j=i 29 R, Comment on the relations and differences between these two time series (i, vi)