Principal Components and Factor Analysis

Abstract

The state.x77 data set is available by default in R; it's a compilation of data about the US states put together from the 1977 Statistical Abstract of the United States, with the actual measurements mostly made a few years before. 1 It's a little long in the tooth now but handy for teaching purposes. The variables are: Population in thouusands Income dollars per capita Illiterarcy Percent of the population Life Exp Years of life expectancy at birth Murder Number of murders and non-negligent manslaughters per 100,000 people HS Grad Percent of adults who were high-school graduates Frost Mean number of days per year with low temperatures below freezing Area In square miles You can do help(state.x77) for a little more detail. There is also a state.center data set, giving the longitude and latitude of the geographic center of each state (except for Alaska and Hawaii, which are artificially put somewhere off the west coast) — see Figures 1 and 2. 1 The Statistical Abstract is " the best book published in America " (P. Krugman), an im-mensely valuable compilation of data about a huge range of aspects of American life, put out every year by the Census Bureau. It's available for free online at