* By Morningstar for The Wall Street Journal. “The Cost of Active Investing,” by Kenneth French, finance professor, Dartmouth College.

* If you’d like to read a whole book on the superiority of indexing and diversification, I have three to recommend: Winning the Loser’s Game: Timeless Strategies for Successful Investing, by the investment consultant Charles Ellis; The Only Guide to a Winning Investment Strategy You’ll Ever Need: The Way Smart Money Invests Today, by Larry Swedroe of Buckingham Asset Management, which manages money for wealthy people; and Unconventional Success: A Fundamental Approach to Personal Investment, by David Swensen, who has made a spectacular success of managing Yale University’s endowment.

* A stock’s market capitalization, or “market cap,” equals the price per share times the number of shares outstanding. Take IBM, with 1.34 billion shares outstanding. On a day when it’s priced at $90, its market cap is $121.9 billion.