PT - JOURNAL ARTICLE AU - Richard Grinold TI - The Description of Portfolios AID - 10.3905/jpm.2011.37.2.015 DP - 2011 Jan 31 TA - The Journal of Portfolio Management PG - 15--30 VI - 37 IP - 2 4099 - https://pm-research.com/content/37/2/15.short 4100 - https://pm-research.com/content/37/2/15.full AB - Grinold provides a general framework for the description of various aspects of a portfolio using a set of factors. The work is cousin to the well-worn topic of performance analysis and attribution, and in that sense, is fairly represented as being old wine in new bottles—the scope is much more general, however. Grinold first provides a theoretical structure with a model that describes various aspects of a portfolio as either the allocation of a portfolio’s variance or as the covariance of two portfolios. He takes a portfolio-centric approach and explains all of the results in terms of the risk and correlation of portfolios. The expanded framework and portfolio focus opens up a wide range of problems that can be studied with the same framework. Grinold uses examples to illustrate what the methodology can accomplish and as a guide to sense when we are asking too much from the model.TOPICS: Portfolio construction, portfolio theory, factor-based models