Moment (mathematics)In mathematics, the moments of a function are certain quantitative measures related to the shape of the function's graph. If the function represents mass density, then the zeroth moment is the total mass, the first moment (normalized by total mass) is the center of mass, and the second moment is the moment of inertia. If the function is a probability distribution, then the first moment is the expected value, the second central moment is the variance, the third standardized moment is the skewness, and the fourth standardized moment is the kurtosis.
Leverage (finance)In finance, leverage (or gearing in the United Kingdom and Australia) is any technique involving borrowing funds to buy things, estimating that future profits will be many times more than the cost of borrowing. This technique is named after a lever in physics, which amplifies a small input force into a greater output force, because successful leverage amplifies the smaller amounts of money needed for borrowing into large amounts of profit. However, the technique also involves the high risk of not being able to pay back a large loan.
Hyperbolic absolute risk aversionIn finance, economics, and decision theory, hyperbolic absolute risk aversion (HARA) refers to a type of risk aversion that is particularly convenient to model mathematically and to obtain empirical predictions from. It refers specifically to a property of von Neumann–Morgenstern utility functions, which are typically functions of final wealth (or some related variable), and which describe a decision-maker's degree of satisfaction with the outcome for wealth. The final outcome for wealth is affected both by random variables and by decisions.
Open market operationIn macroeconomics, an open market operation (OMO) is an activity by a central bank to give (or take) liquidity in its currency to (or from) a bank or a group of banks. The central bank can either buy or sell government bonds (or other financial assets) in the open market (this is where the name was historically derived from) or, in what is now mostly the preferred solution, enter into a repo or secured lending transaction with a commercial bank: the central bank gives the money as a deposit for a defined period and synchronously takes an eligible asset as collateral.
