The data of Table 9.1 relate the number of motor vehicle deaths occurring in 12 counties in the northwestern United States in the years 1988 and 1989.

A glance at Figure 9.8 indicates that in 1989 there was, for the most part, a reduction in the number of deaths in those counties that had a large number of motor deaths in 1988.

Similarly, there appears to have been an increase in those counties that had a low value in 1988. Thus, we would expect that a regression to the mean is in effect. In fact, running Program 9.2 yields that the estimated regression equation is

showing that the estimated value of β indeed appears to be less than 1.

Transcribed Image Text:

y=74.589+.276x