This is a textbook for the standard undergraduate econometrics course. Its only prerequisites are a semester course in statistics and one in differential calculus. Arthur Goldberger views the subject as a tool of empirical enquiry rather than as a collection of arcane procedures. The central issue in such an inquiry is how one variable is related to one or more others. Goldberger takes this to mean "how does the average values of one variable vary with one or more others?", and so takes the population conditional mean function as the target of empirical research. To help students master the tools of econometrics, Goldberger provides many theoretical and empirical exercises and, on an accompanying diskette, real micro- and macroeconomic data sets. The data sets deals with earnings and education, money demand, firm investment, stock prices, compensation and productivity, and the Phillips curve. INDICE Empirical relations fitting the data univariate populations bivariate populations inference about a population mean classical regression model inference in the classical model prediction and fit multiple regression - preliminaries multiple regression - classical model multiple regression - applications multiple regression - general case relaxing the assumptions of the classical model heteroskedasticity autocorrelation -preliminaries regression with autocorrelation binary response models simultaneity - preliminaries models of demand and supply estimation of simultaneous-equation models.