Equity premium puzzleThe equity premium puzzle refers to the inability of an important class of economic models to explain the average equity risk premium (ERP) provided by a diversified portfolio of U.S. equities over that of U.S. Treasury Bills, which has been observed for more than 100 years. There is a significant disparity between returns produced by stocks compared to returns produced by government treasury bills. The equity premium puzzle addresses the difficulty in understanding and explaining this disparity.
Heavy crude oilHeavy crude oil (or extra heavy crude oil) is highly viscous oil that cannot easily flow from production wells under normal reservoir conditions. It is referred to as "heavy" because its density or specific gravity is higher than that of light crude oil. Heavy crude oil has been defined as any liquid petroleum with an API gravity less than 20°. Physical properties that differ between heavy crude oils and lighter grades include higher viscosity and specific gravity, as well as higher molecular weight hydrocarbon composition.
Economic puzzleA puzzle in economics is a situation where the implication of theory is inconsistent with observed economic data. An example is the equity premium puzzle, which relates to the fact that over the last two hundred years, the risk premium of stocks over bonds has been around 5.5%, much larger than expected from theory. The equity premium puzzle was first documented by Mehra and Prescot (1985). See also ; Financial economics #Challenges and criticism. Equity premium puzzle Home bias in trade puzzle Equity home
Rente de situationUne rente de situation est un surplus de rentabilité (parfois appelé surprofit) qu'obtient une entreprise ayant un avantage compétitif. Cet avantage peut venir : d'une plus grande efficacité technique : coûts moindres, produits et services plus attractifs (différenciation) ; ou d'une meilleure situation sur le marché : position de monopole ou de leader en part de marché, marque plus connue ou mieux perçue, accès privilégié à certaines ressources ou débouchés, etc. On peut parler dans ce cas de concurrence imparfaite.
