2.51 Table below lists the U.S. retail gasoline price

(cents per gallon) and U.S. FOB cost of crude oil

(dollars per barrel) as reported by the U.S.

Energy Information Administration (http://www

.eia.doe.gov/).

a Construct a scatterplot of gasoline prices versus crude oil prices. Describe the nature of the relation.
b Estimate the relation using the least-squares technique.
c Construct a residual plot.
d Comment on the appropriateness of the linear relation between gasoline and crude oil prices.

for different parameter (xa) values are reported in table below (read from a chart).

a Fit a simple linear regression model to the relation between the stress and the parameter xa.
b Assess the strength of the estimated relation.
c Is a linear or nonlinear model more appropriate?
d Using the model you choose, predict the hoop stress level for xa 0.30.

Transcribed Image Text:

Crude Year Oil Gasoline Year Crude Oil Gasoline 1984 27.60 91.6 1995 15.69 76.1 1985 25.84 91.9 1996 19.32 84.3 1986 12.52 63.7 1997 16.94 83.1 1987 16.69 67.7 1998 10.76 66.0 1989 16.89 76.8 1999 16.47 76.2 1990 20.37 89.9 2000 26.27 109.1 1991 16.89 81.8 2001 20.46 102.2 1992 16.77 78.7 2002 22.63 94.3 1993 14.71 75.3 2003 25.86 113.5 1994 14.18 72.9 2004 33.75 142.3