In an editorial of Nature called "Portfolio boost" (PDF version available here) and published on August 20th, 2015, they  recommand to read an article of Wallace and Rafols, "Research Portfolio Analysis in Science Policy: Moving from Financial Returns to Societal Benefits", saying:

"Such are the virtues of research-portfolio analysis. Those intrigued by such mindfulness should turn to a study (M. L. Wallace and I. Rafols Minerva 53, 89–115; 2015) that looks at relevant literature from recent decades, and highlights the benefits of inward-looking analysis that also creates opportunities for transparency and stakeholder engagement. The study highlights the limitations of corporate approaches to portfolio analysis that are geared to financial returns and well-defined markets — in contrast to the broader aims of government, philanthropic funders and universities."