Reasonably intelligent people can find many ways to screw up their personal finances. The New York Times identifies six of them.

1. I.Q. "Just because you can solve doctoral-level math problems in the realm of data science does not mean you can also pick stocks that will outperform the rest of the market," the Times notes.

2. Return Entitlement. Some investors think they're going to achieve a certain return, just because they heard that someone else achieved it.

Editor's Note: Seniors Scoop Up Unclaimed $20,500 Checks? (See if You qualify)

3. The Next Cubicle. Constantly comparing your salary to your co-worker's isn't going to push yours higher.

4. Pretax Dollars. Remember that your Social Security income is taxable.

5. Monthly Debt. If your debt is more than 2.25 times your income, you've got problems, Charles Farrell, a Denver financial adviser, told The Times.

6. Neutered Numbers. Some people are too emotional about money to accept the numerical truth of their financial situation.

For those who are close to retirement or preparing for retirement, Bankrate.com cites seven common investing mistakes that you'd do well to avoid.

• "Not taking full advantage of tax breaks.

• "Not saving enough—or at all.

• "High fees in retirement plans and investments.

• "Focusing on only one risk.

• "Investing aimlessly.

• "Retiring with no plan for income.

• "Holding on to the hoarding mentality."

Editor's Note: Seniors Scoop Up Unclaimed $20,500 Checks? (See if You qualify)

Related Articles:

• Forbes: Staying on the Job for Years Costs Americans Big Money
• Author Michael Lewis: 'The Most Iconic Market in Global Capitalism Is Rigged'