The extent to which any variable is spread out rather than concentrated at some particular value. Dispersion can be measured in various ways. The range is simply the difference between the highest and lowest values. This is usually not regarded as a satisfactory measure, as it disregards the distribution of all other values, while the extreme values themselves may be outliers due to freaks or errors of measurement. A commonly used measure of dispersion is the standard deviation, which is defined as the square root of the mean of squared deviations of the variable from its own mean. Thus if x takes N different values, x_i for i = 1, 2, …, N, with mean μ, the standard deviation is given by 0198607679.dispersion.1.jpg To allow for the fact that different variables have different means, comparisons of dispersion frequently use the coefficient of variation, which is the ratio of the standard deviation to the mean, or v = σ/μ. This is not satisfactory when x can take negative values, so that its mean may be small or negative.

• exchange rate
• exchange rate bands
• Exchange Rate Mechanism
• exchange rate regime
• exchange restrictions
• excise duty
• exclusion
• exclusive dealing
• ex dividend
• executive, chief
• exercise price
• exhaustible resources
• Eximbank
• exit
• exit, freedom of
• exit price
• exogenous expectations
• expectations
• expectations-augmented Phillips curve
• expectations, model-consistent
• expected inflation
• expected utility
• expected value
• expenditure
• expenditure-based deflator