A consumer group collected information on HDTVs . They created a linear model to estimate the cost of an HDTV (in ) based on the screen size (in inches). Which is the most likely value of the slope of the line of best fit?
A) 70 B) 7000 C) 0.70 D) 700 E) 7
Q. 2The correlation between X and Y is r = 0.35. If we double each X value, decrease each Y by 0.20, and interchange the variables (put X on the Y-axis and vice versa), the new correlation
A) is 0.70.
B) is 0.90.
C) cannot be determined.
D) is 0.35.
E) is 0.50.
Q. 3The auto insurance industry crashed some test vehicles into a cement barrier at speeds of 5 to 25 mph to investigate the amount of damage to the cars.
They found a correlation of r = 0.60 between speed (MPH) and damage (). If the speed at which a car hit the barrier is 1.5 standard deviations above the mean speed, we expect the damage to be _?__ the mean damage.
A) 0.60 SD above
B) equal to
C) 0.90 SD above
D) 1.5 SD above
E) 0.36 SD above
Q. 4Do you think a model based on these data could accurately predict the average number of strikeouts for a pitcher with an average fastball speed of 70 mph.? Explain.
What will be an ideal response?
Q. 5Do you think the association would be stronger or weaker if we used data from one month of the season?
What will be an ideal response?
Q. 6Do you think there is a pattern? Describe the association between speed and the number of strikeouts.
What will be an ideal response?
Q. 7Comment on any unusual data point or points in the data set. Explain.
What will be an ideal response?
Q. 8Do you think there is a clear pattern? Describe the association between fiber and calories.
What will be an ideal response?