This is a simple data set provided by Chatterjee and Price (1977, p. 108) that serves as a known example of heteroscedasticity.
Format
A data frame with 50 observations on the following 6 variables.
state
a character vector for the state
region
a character vector for the Census region
urbanpop
a numeric vector for the number of residents (per thousand) living in urban areas in 1970
incpc
a numeric vector for income per capita in 1973
pop
a numeric vector for residents (per thousand) under 18 years of age in 1974
edexppc
a numeric vector for per capita public school expenditures in a state, projected for 1975.