More on an Empirical Definition of Money: Note
评估了Kaufman对Friedman和Meiselman货币经验定义方法的扩展，通过分析不同金融总量与GNP的相关性及滞后关系，发现货币的最佳定义取决于其领先或滞后GNP的季度数。
This study was conducted to evaluate George Kaufman's extension of the Friedman and Meiselman technique for an empirical definition of money. This method defines as money that financial aggregate which satisfies two criteria: 1) it exhibits the highest correlation with GNP, and 2) the correlations between GNP and each of the components considered separately do not exceed that between GNP and the aggregate. The components are thus substitutes the public alters the composition of its portfolio due to changes in supply conditions, while keeping its portfolio size constant relative to GNP. (See Friedman and Schwartz, ch. 2; and J. R. Hicks, p. 49.) The set of assets heretofore considered include liquid financial assets. Friedman and Meiselman discovered that the dual criteria were best satisfied by the sum of currency and all privately held deposits at commercial banks (pp. 182-84). Kaufman examined the proposition that if money is a factor in determining GNP, its effect may be delayed by as long as a year. From correlations between GNP and various financial aggregates which led GNP by +4 to -2 quarters, he found that the best definition of money depends on the number of quarters by which the financial measure leads or lags GNP. In general, the broader aggregates perform better when they are observed two or more quarters before income while the narrow definition performs best when observed concurrently with income (see Kaufman, pp. 86-87, Tables 1 and 2). Kaufman examines the impact of changes in the monetary aggregate on changes in income in a particular current or future quarter, a procedure which is appropriate if money's effect on income occurs with a discrete time lag. The present study, extends the Kaufman analysis, allowing the effect of money on GNP to be distributed over several quarters by examining regressions of the following form: