An entity whose income exceeds its expenditure can lend or invest the excess income. On the other hand, an entity whose income is less than its expenditure can raise capital by borrowing or selling equity claims, decreasing its expenses, or increasing its income.

Researchers in experimental finance can study to what extent existing financial economics theory makes valid predictions, and lick to Financial Planning discover new principles on which such dogma can be extended. Research may proceed by conducting trading simulations or by establishing and studying the behaviour of people in artificial competitive market-like settings.