Based on the residual plot, is the linear model appropriate?
Jim has started a new exercise program. He has
monthly checkups where his percentage of body fat is
measured. Jim records his body fat percentage and
the number of months he has been on the exercise
program. He collects data for 10 months and finds a
linear model to give the relationship between the time
spent exercising and his percentage of body fat. The
equation of the line is y = 17 -1.25x, where y is his
percentage of body fat and x is the time spent
exercising (in months). The residual plot is shown
O No, there is no clear pattern in the residual plot.
Yes, there is no clear pattern in the residual plot.
O No, there is a clear pattern in the residual plot,
indicating that the linear model is not appropriate.
o Yes, his percentage of body fat clearly decreases
for the first four months and then increases after
that
Residual
2