This App Tells You What Your Friends Invest In. Is That a Good Thing?

The best way to monitor your investment portfolio is probably to monitor it not very much at all. The Set It and Forget It approach says that once you’ve made choices about how much risk you’re comfortable with, constantly checking returns can be harmful—that thrilling over today’s gain and despairing over tomorrow’s loss is not just stressful but encourages bad financial behavior. Betterment, the online investment service, recently posted a good rundown of why this is the case. The more often a person checks his portfolio, the more risky he perceives it to be, and the more likely he is to make decisions based on emotion, buying high and selling low. Betterment believes in this so much that it may be the only startup that wants some clients to use its app and website less. It refers to those who log in less than once a month as “superstars,” and says users who monitor their portfolios as often as every other day “are likely stressing themselves out needlessly, without any improvement in performance.”

However, for many investors, that’s tough advice to follow—especially at wild times like right now. The Treasury market freaked out on Oct. 15 in a way it hasn’t since the fall of Lehman Bros., and on half the trading days in October, stocks have moved more than 1 percent in a single session. Which investments are holding up? Which are cratering? Am I an idiot or a genius for having this or that allocation to equities?