Page 343 - Applied Statistics with R
P. 343
14.2. PREDICTOR TRANSFORMATION 343
Fitted versus Residuals Normal Q-Q Plot
50000 50000
Residuals 0 Sample Quantiles 0
-50000 -50000
50000 100000 150000 200000 -2 -1 0 1 2
Fitted Theoretical Quantiles
initech_fit_log = lm(log(salary) ~ years, data = initech)
log( ) = + +
1
0
plot(log(salary) ~ years, data = initech, col = "grey", pch = 20, cex = 1.5,
main = "Salaries at Initech, By Seniority")
abline(initech_fit_log, col = "darkorange", lwd = 2)
Salaries at Initech, By Seniority
12.5
12.0
log(salary) 11.5
11.0
10.5
5 10 15 20 25
years
