According to a Harris Interactive survey, 70% of Americans don't expect the economy to improve in the coming year. Before you panic, remember that a whole pile of surveys just like this one have consistently revealed one striking truth: Most people don't know enough about finance or economics to have an informed opinion on either subject. That bodes poorly for their market predictions, but it can spell even worse news for their own investments.

These recent surveys only confirm that too many people have too little knowledge about money:

  • The Finra Investor Education Foundation found that only one in five people knew that when interest rates rise, bond prices fall. Among those who earn more than $75,000 annually, 46% don't compare prices when getting a car loan.
  • A 2009 Finra Financial Capability study found that 17% of defined contribution plan participants didn't know whether they held stocks or stock mutual funds in their retirement plan.
  • The National Foundation for Credit Counseling's (NFCC) Financial Literacy Survey for 2010 found that a third of Americans are not saving money for retirement, and 30% report having no savings.
  • The folks at Financial Finesse note that 53% of those they surveyed say they lack a basic knowledge of stocks, bonds, and mutual funds.

This is an abysmal showing, but it's also sadly understandable. Few of us ever learned about financial matters in school, or from investing role models.

Making big retirement mistakes
Retirement plan investing can be particularly tough to grasp. Even those who do participate in a 401(k) or other plan may be exposed to too much risk, if they have too much of their money invested in their company's stock.

At many companies, workers have responded to falling share prices by suing their employers for poor stock performance. RadioShack (NYSE: RSH) has been sued for having too much of its retirement assets in company stock, which has lost an average of 7.6% annually over the past decade (though the past few years have seen gains). Even Coca-Cola (NYSE: KO) got sued several years ago for having too much of its own stock in its 401(k) plan -- some 57%, as of 2005.

In some cases, high concentrations of company stock come about because the companies themselves contribute stock as part of matching contributions. But all too often, workers are the ones choosing too much stock. Many companies, including Bristol-Myers Squibb (NYSE: BMY) and Cigna (NYSE: CI), are now taking steps to help and encourage workers to reduce their exposure to company stock, if only to reduce the chance that they'll one day wind up in court.

The solution
We'd all be better off spending less time listening to -- or making -- ill-informed financial predictions, and more time educating ourselves about ways to improve our own investments. True, most of us aren't qualified economic prognosticators. But that doesn't mean we can't become successful investors. 

Dividends are great for retirement. Check out these promising stocks.

Longtime Fool contributor Selena Maranjian owns shares of Coca-Cola. The Fool also owns shares of Coca-Cola, which is a Motley Fool Inside Value pick and a Motley Fool Income Investor selection. Try any of our investing newsletter services free for 30 days. The Motley Fool is Fools writing for Fools.