Longley's Economic Regression Data
A macroeconomic data set which provides a well-known example for a highly collinear regression.
A data frame with 7 economical variables, observed yearly from 1947 to 1962 ($n=16$).
- GNP implicit price deflator ($1954=100$)
- Gross National Product.
- number of unemployed.
- number of people in the armed forces.
- noninstitutionalized population $\ge$ 14 years of age.
- the year (time).
- number of people employed.
lm(Employed ~ .)is known to be highly collinear.
J. W. Longley (1967) An appraisal of least-squares programs from the point of view of the user. Journal of the American Statistical Association 62, 819--841.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
require(stats); require(graphics) ## give the data set in the form it is used in S-PLUS: longley.x <- data.matrix(longley[, 1:6]) longley.y <- longley[, "Employed"] pairs(longley, main = "longley data") summary(fm1 <- lm(Employed ~ ., data = longley)) opar <- par(mfrow = c(2, 2), oma = c(0, 0, 1.1, 0), mar = c(4.1, 4.1, 2.1, 1.1)) plot(fm1) par(opar)