The accompanying data were read from graphs that appeared in the article “Bush Timber Proposal Runs Coun ter to the Record” (San Luis Obispo Tribune, Sep tem ber 22, 2002). The variables shown are the number of acres burned in forest fires in the western United States and timber sales.

Year Number of Acres Burned

(thousands)

Timber Sales

(billions of board feet)

1945 200 2.0 1950 250 3.7 1955 260 4.4 1960 380 6.8 1965 80 9.7 1970 450 11.0 1975 180 11.0 1980 240 10.2 1985 440 10.0 1990 400 11.0 1995 180 3.8

a. Is there a correlation between timber sales and acres burned in forest fires? Compute and interpret the value of the correlation coef fi cient.

b. The article concludes that “heavier logging led to large forest fires.” Do you think this conclusion is jus ti fied based on the given data? Explain.