How Personality Traits Affect Successful Financial Investments You'll earn a higher return on investments if you know a little "money psychology." Here are four ways personality traits affect your thoughts and behaviors about money. Knowing the psychology behind your financial investments - and how personality traits affect your investment portfolio - can change the way you invest in low-risk mutual funds, medium-to-high risk stocks and bonds, or your company's 401K plan. Navigate: Investment Theories ... Investment Strategies ... Trading Rules... (edit) __NOEDITSECTION__