Introduction to Simple Linear Regression

An introduction to simple linear regression. The pain-empathy data is estimated from a figure given in: Singer et al. (2004). Empathy for pain involves the affective but not sensory components of pain. Science, 303:1157--1162. The Janka hardness-density data is found in: Hand, D.J., Daly, F. , Lunn, A.D., McConway, K., and Ostrowski, E., editors (1994). The Handbook of Small Data Sets. Chapman \& Hall, London. Original source: Williams, E.J. (1959). Regression Analysis. John Wiley \& Sons, New York. Page 43, Table 3.7.