Today the dominant form of economic organization at the world level is based on market-oriented mixed economies.• Paul A. Samuelson and William D. Nordhaus (2004). Economics, McGraw-Hill, Glossary of Terms, "Mixed economy"; ch. 1, (section) Market, Command, and Mixed Economies.• Alan V. Deardorff (2006). Glossary of International Economics, Mixed economy. An economic system can be considered a part of the social system and hierarchically equal to the law system, political system, cultural and so on. There is often a strong correlation between certain ideologies, political systems and certain economic systems (for example, consider the meanings of the term "communism"). Many economic systems overlap each other in various areas (for example, the term "mixed economy" can be argued to include elements from various systems). There are also various mutually exclusive hierarchical categorizations.
