Pfau, Bruce. "Watson Wyatt's Human Capital Index: Human Capital As a Lead Indicator of Shareholder Value." Watson Wyatt Worldwide, 2001.

Constructs an index of human resource measures believed to be correlated with stock market performance, and finds that companies with high scores on this index had higher market valuations (as measured by price/book ratio) than companies with lower scores. Moreover, by comparing the firms' 1999 scores and market values with their 2001 scores and market values, the researchers find that "superior human capital practices are not only correlated with financial returns they are, in fact, a leading indicator of increased shareholder value."