It’s hard to quarrel with advice to become more educated, but some learning exercises aren’t helpful.

One of the most difficult aspects of investing involves sifting through the daily barrage of advice offered by experts. More often than not, this advice is calculated to enrich the securities industry at your expense. One way to determine whether investment advice has merit is to ask for the data on which an assertion is based. More often than not, there is no data. The expert is merely offering an opinion, which may or may not be accurate.

A recent article, written by staff at the Motley Fool and published on CNNMoney, is illustrative. The purpose of the article was to inform investors of the most important investment principles they should be applying. The source of advice is three Motley Fool experts.

Let’s take a closer look at their views:

Jordan Wathen. The first of the three experts, Jordan Wathen, does not get off to a good start. Wathen is a big fan of Seth Klarman, who he believes is one of the world’s best hedge fund managers.” Why anyone would rely on the expertise of hedge fund managers. given their appalling returns, is a mystery. Larry Swedroe, director of research for the BAM Alliance, pointed to several studies for evidence of why they make an unwise investment in a December 2014 ETF.com article.

Wathen is also a fan of Klarman’s book, Margin of Safety: Risk-Averse Value Investing Strategies for the Thoughtful Investor. He particularly likes the advice to “focus on what you can know.” He believes this simple idea can earn you fantastic results in the stock market. Should you, as an investor, follow this advice? A 2010 study, Do Individual Investors Have Asymmetric Information Based on Work Experience by Trond Doskeland and Hans Hvide, found that investors who bought stocks in industries in which they worked (and presumably were very familiar with) underperformed investors who didn’t work in those industries.

Picking stocks based upon what you know has other perils, depending on the breadth of your knowledge. If your knowledge is limited to your geographic area or to what you read in the financial news, your portfolio may not be appropriately diversified. For example, you may not be aware of companies in emerging markets or of other foreign stocks.

Your familiarity with a particular company may also cause you to underestimate the risk of investing in that company.

Finally, whatever you know about a particular company is already known to the markets and in the public domain. That information has been assessed by millions of professional traders and other investors. Those investors have incorporated that information into the price of the stock of that company. As such, when you buy any publicly traded company, it is likely the price is a fair one.

I am aware of no credible evidence supporting the view that knowing something about a company is a responsible or intelligent basis for making investment decisions.

Selena Maranjian. Another Motley Fool expert, Selena Maranjian, counsels investors to learn, learn, learn… and keep learning. It’s hard to quarrel with advice to become a more educated investor, but many investors engage in counterproductive learning exercises, such as doing research on individual stocks. There are many resources available that could help you achieve higher expected returns, but they are rarely mentioned when experts tell you to learn.

If you have the time to read an excellent investing book, I highly recommend The Little Book of Common Sense Investing by John Bogle. If you want to maximize your time and come away a better investor than many of the professionals, you should read If You Can: How Millennials Can Get Rich Slowly by William Bernstein. This mini-book is only about 50 pages and packed with investing wisdom.

The bottom line regarding what you should learn about investing is neither complex nor time-consuming. Focus on your asset allocation (the division of your portfolio between stocks and bonds). Invest in a globally diversified portfolio of low-management fee index funds, exchange-traded funds (ETFs) or passively managed funds. Avoid using any broker or advisor who claims to be able to beat the market.

Dan Dzombak. Dzombak tells investors to follow the teaching of Ben Graham, who introduced the motto margin of safety in his classic investing book, The Intelligent Investor. Dzombak interprets this motto as buying an investment at less than its intrinsic value, or earning power, while using conservative assumptions.

I suspect this kind of intricate analysis is far beyond the ability of most investors. It also ignores the fact, as set forth above, that most stocks are priced fairly. If you are looking for simplicity, ease of implementation and the potential for expected returns higher than the vast majority of investors, I have some good news for you.

Consider buying an exchange-traded fund, such as Vanguard Total World Stock ETF. With this one fund, you will capture the returns of the global stock market, at very little cost (it has an expense ratio of 0.18 percent). For the bond portion of your portfolio. consider Vanguard Short-Term Government Bond ETF. It also has a very low expense ratio of just 0.12 percent.

Rebalance your portfolio once or twice a year to be sure your risk level remains within your tolerance. Then ignore the financial news and stick to a disciplined buy-and-hold strategy. You are now done learning. And you are likely to outperform most investors who engage in stock picking, market timing and attempts to pick the next “hot” mutual fund manager.

You will also sleep better at night.

Dan Solin is the director of investor advocacy for the BAM ALLIANCE and a wealth advisor with Buckingham. He is a New York Times best-selling author of the Smartest series of books. His latest book is The Smartest Sales Book You’ll Ever Read.