a volatility - based securities index framework solves problems with the prior art . by recognizing that investors share the rational goal of earning the highest level of return for any level or risk , a volatility - based index provides investors with information about the most distinct choices in risk . compared to known approaches , a volatility - based index framework partitions a securities market into much more differentiated segments which in turn provide much more distinct investment choices . further , within each volatility segment , constituent members are more homogeneous facilitating a clearer understanding of each group &# 39 ; s relative attractiveness . at an asset allocation level , improved risk choices expand opportunities to convert poorly compensated high risk investments into more attractive investments elsewhere . the persistence of volatility maintains style distinctions effectively over time , offering significant protection to tax exposed investors .